DigitalUM :: Browsing by Subject "Rat"

Browsing by Subject "Rat"

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A computerized analysis of the entire retinal ganglion cell population and its spatial distribution in adult rats
(Elsevier, 2009-01) Mayor Torroglosa, S.; Jiménez López, M.; Avilés Trigueros, Marcelino; Holmes, T. M.; Lund, R. D.; Villegas Pérez, M. P.; Vidal Sanz, M.; Salinas Navarro, Manuel Ángel; Anatomía Humana y Psicobiología
In adult albino (SD) and pigmented (PVG) rats the entire population of retinal ganglion cells (RGCs) was quantified and their spatial distribution analyzed using a computerized technique. RGCs were back-labelled from the optic nerves (ON) or the superior colliculi (SCi) with Fluorogold (FG). Numbers of RGCs labelled from the ON [SD: 82,818 ± 3,949, n = 27; PVG: 89,241 ± 3,576, n = 6) were comparable to those labelled from the SCi [SD: 81,486 ± 4,340, n = 37; PVG: 87,229 ± 3,199; n = 59]. Detailed methodology to provide cell density information at small scales demonstrated the presence of a horizontal region in the dorsal retina with highest densities, resembling a visual streak.
Open Access
Age and experimental obstructive emphysema. A morphometrical study on the rat
(Murcia : F. Hernández, 1995) Escolar Castellón, J.de D.; Gallego, B.; Escolar, M.A.; Miñana Amada, C.; Roche, M.
Age, as a risk factor in the development of experimental obstructive emphysema, is proposed as the hypothesis of this study. Ninety-two Wistar rats were organized into two age groups: adult (16 weeks) and middle-aged (56 weeks). Each age group was subdivided into three groups: a control group, consisting of unmanipulated animals; a «cannula» group consisting of animals into whose trachea a cannula was implanted; and a «valve» group, consisting of animals into whose trachea a valve had been implanted. The survival was one month. A histomorphometric study was performed on the lungs and the results were compared statistically. 1-hroughout the experiment the amount of food consuni~~byi each animal and the variations in weight were monitored. After sacrifice, the lungs were processed for light microscopy. Thirteen histomorphometric variables were quantified and subsequently systematized into three groups: those which quantified the size of' Iie distal airspace («=ea of the al; ;)!:ir seci .: .,: ,.. , ., . lar chordn and «mean linear interct:l>i . . il~o.,civ hich quantified the tissue («wall tliicknt. - % : : : ,sue density», «interna1 perimeter of eacii ::i\ :c>liii- \c.i,iioii),, <(interna1 alveolar perimeter per fielcl>, ~ i i i ~.,;a lvcolar section/section perimetern); and those which quantified the elastic fibre («elastic fibre area», «elastic fibre perimeter», «elastic fibre area/elastic fibre perimeter», selastic fibre density» and «elastic fibre density per tissue density»). The results were compared statistically and the sensitivity, specificity and misclassification indices were calculated, as well as the attributable and relative risk. From the results, it was observed that, in general, the animals of the valve and cannula groups in both age groups displayed a decrease in food intake and a body weight loss. The middle-aged animals were the only group which displayed significant differences in al1 the morphometric variables except wall thickness, when the cannula and valve groups were compared with the control group. In both the cannula and valve groups, the Offprint [equests to: Dr. Juan de Dios Escolar, Departamento de Ciencias Morfológicas, Facultad de Medicina, 50009 Zaragoza, Spain values of the variables which quantified the distal airspace increased, while the values of the variables which quantified the lung tissue and the elastic fibre decreased. In the manipulated middle-aged group, the attributable risk of developing emphysema was 56.66% and the relative risk 5.55; in the group of manipulated adult animals, the attributable risk was 23.55% and the relative risk 1.66. The results of this study lead us to propose that the middle-aged rats with experimental airflow obstruction displayed a greater risk of developing emphysema than the adult rats which were subjected to the same procedure.
Open Access
Age- and sex-associated changes in prosaposin and its receptors in the lacrimal glands of rats.
(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2020) Islam, Farzana; Khan, Md. Sakirul Islam; Nabeka, Hiroaki; Shimokawa, Tetsuya; Yamamiya, Kimiko; Matsuda, Seiji
Prosaposin, a saposin precursor, is a potent neurotrophic factor found in several tissues and various biological fluids. Saposin-deficient patients have different ophthalmic disorders, indicating a relationship between ocular health and prosaposin. However, there is little information about prosaposin on the ocular surface. Because ocular functions are diverse and depend on age and sex, we examined whether prosaposin and its receptors, G protein-coupled receptor 37 (GPR37) and GPR37L1, are expressed in the major ocular glands, the extra orbital lacrimal gland (ELG), and harderian gland (HG) of rats and whether sex and aging affect their expression. Immunohistochemical analyses revealed that prosaposin and its receptors were expressed in the ELGs and HGs of rats, although their expression varied based on the type of gland, age, and sex. Prosaposin, GPR37, and GPR37L1 were expressed in the basolateral membranes and cytoplasm of acinar cells of the ELGs, and their immunoreactivities were higher in female rats of menopausal age than age-matched male rats. However, such age- and sex-related differences in the immunoreactivities of prosaposin, GPR37, and GPR37L1 were not observed in the HGs. Triple immunofluorescence labelling revealed that prosaposin, GPR37, and GPR37L1 were co-localised in the acinar and ductal cells in the ELGs, although the degrees of colocalization varied according to the age and sex of the rats. Together, the present results showed that prosaposin and its receptors were expressed in the major ocular glands of rats, and their immunoreactivities to the ELGs differed considerably with age and sex.
Open Access
Alleviative effect of myricetin on ochratoxin A-induced oxidative stress in rat renal cortex: histological and biochemical study
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2016) Abd El-haleem, Manal R.; Kattaia, Asmaa A.A.; Abd El-Baset, Samia A.; El Sayed Mostafa, Heba
Ochratoxins (OTA) are secondary metabolites of Aspergillus and Penicillium. The detoxification of OTA has been of major interest due to its widespread threat to human health. We aimed to investigate the possible alleviative effect of myricetin (MYR) against OTA-induced damage in renal cortex of rats. Thirty adult male albino rats were randomized into five equal groups: control (untreated), vehicle control (0.5 ml corn oil/day including dimethylsulfoxide [DMSO]), MYR (100 mg MYR/kg b.w./day in distilled water), OTA (0.5 mg OTA/kg b.w./day; dissolved in 10% DMSO and then corn oil) and OTA + MYR group (received OTA and MYR at similar doses). All treatments were given by oral gavage for 2 weeks. At the end of the experiment, renal cortices were processed for light and electron microscope examinations. Immunohistochemical staining for localization of proliferating cell nuclear antigen (PCNA), p53 and transforming growth factor beta 1 (TGF-β1) was carried out. Biochemical analysis of tissue glutathione peroxidase (GPX), catalase (CAT) and superoxide dismutase (SOD) were determined to evaluate oxidative stress. OTA administration induced deleterious renal injury evidenced by the structural and ultra-structural changes. Immunohistochemical expression of p53, PCNA and TGF-β1 were significantly up regulated compared with control. Alterations in antioxidant parameters supported that oxidative stress was one of the mechanisms involved in OTA toxicity. On the contrary, co-administration of MRY partially ameliorated OTAinduced renal injury. We suggest the potential effectiveness of MYR to counteract OTA-induced toxic oxidative stress on the renal cortex.
Open Access
Alterations induced by cyclosporine A in myocardial fibers and extracellular matrix in rat
(Murcia : F. Hernández, 2002) Rezzani, R.; Angoscini, P.; Rodella, L.F.; Bianchi, R.
Cyclosporine A (CsA) is the first choice immunosuppressant universally used in allotransplantation. However, it has been demonstrated that this drug produces unwanted side effects in several organs and in particular in the kidney and in the heart. While the cardiac toxicity, due to alteration of myocardial prostanoid has been reported, no data are available about the effects of CsA on myocardial cytoarchitecture. We studied the CsA induced alterations of the myocardial structure and of the extracellular matrix components (ECM). To test the ECM enzymatic changes we studied a family of enzymes (matrix metalloproteinase-MMP), responsible for the degradation of extracellular matrix components. In particular we investigated MMP1, MMP2 and MMP9. The study was carried out on two groups of Wistar rats. The group I animals served as a control and were injected subcutaneously daily with castor oil for 21 days. Group II: animals were subcutaneously injected daily with CsA (dose: 15 mg/Kg in castor oil) for 21 days. The group I animals (control) had normal heart architecture and low levels of MMP1, MMP2 and MMP9. The group II animals showed degenerative changes with myocardial fibrosis, low levels of MMP1 and MMP9 but a clear increase in MMP2. We suggest that the myocardial fibrosis was a consequence of the cardiotoxic effect of CsA determining the alteration of the balance between synthesis and degradation of ECM. The increase in MMP2 suggests that this enzyme could play a protective role during myocardial damage and represent a compensatory mechanism for the excessive accumulation of collagen.
Open Access
Bronchial-associated lymphoid tissue (BALT) response to airway challenge with cigarette smoke,bovine antigen and anti-pulmonary serum
(Murcia : F. Hernández, 1992) Escolar Castellón, J.de D.; Escolar castellón, A.; Roche Roche, P.A.; Miñana Amada, C.
The bronchial-associated lymphoid tissue (BALT) is a lymphoepithelial organ, related to the immune defence of the lung and to alveolar clearance, which changes size in certain states of disease. Changes in the size of BALT were quantified and compared, and Spearman's test was used to test the relation with the bronchial epithelium. A total of 180 rats were used, divided into 6 groups of 30 as follows: 1) untreated controls; 2) exposed to cigarette smoke for two months; 3) treated with antipulmonary serum three doses daily over five days; 4) exposed to cigarette smoke and treated with antipulmonary serum; 5) sensitized with bovine albumin and exposed to an environment containing this antigen for two months; 6) exposed to cigarette smoke and bovine albumin. The lungs were processed for histological study, and were stained with the PAS-Alcian blue method. The main left bronchi BALT was studied, and the following were quantified: Lymphatic area (LA), as a percentage of the lung surface occupied by BALT; the flat epithelium (FEp), as the length of bronchial epithelium anatomically related to LA, whose cells tend to adopt a flat shape; the Contact epithelium (Cep), as the length of bronchial epithelium which is in direct contact with the LA. A percentage count of bronchial cells was made in the following classifications: globet cells; globet cells stained with the PAS-Alcian blue method; flat cells; lymphoepithelium cells; columnar cells; and bronchial epithelium cells excluding the above two cell types. The most outstanding findings were that, in comparison with the controls, the FEp and CEp had increased in al1 the treated animals, and the CEp of the group treated with bovine albumin + cigarette smoke was the only one in which the difference was Offprint requests to: Dr. D. Juan de Dios Escolar Castellón, Facultad de Medicina, C./ Domingo Miral s/n, 50009 Zaragoza, Spain not significant (p > 0.05). The lymphatic area increased significantly (p < 0.001) in the groups treated with cigarette smoke, anti-pulmonary serum and cigarette smoke + anti-pulmonary serum, and decreased (p > 0.05) in the one treated with bovine albumin. Regression analysis gave good indices in general (Rho > 0.06), the exception being the group treated with cigarette smoke + ALS, in the relations CEpJFEp and CEpILA (Rho < 0.06). The globet ceiis decreased significantly in al1 the treated animals; however, the correlation between globet cells and the other variables did not give good indices (Rho > 0.06). Therefore, it is deduced that BALT can change shape in different conditions, FEp being the variable which increases most. The fa11 in globet ceiis is associated exclusively with the substances which were administered, since no relation was found between these cells and the morphological changes in the BALT.
Open Access
Ccdc85C, a causative protein for hydrocephalus and subcortical heterotopia, is expressed in the systemic epithelia with proliferative activity in rats
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2015) Tanaka, Natsuki; Izawa, Takeshi; Takenaka, Shigeo; Yamate, Jyoji; Kuwamura, Mitsuru
. Coiled-coil domain containing 85c (Ccdc85c) is a causative gene for spontaneous mutant mouse with non-obstructive hydrocephalus and subcortical heterotopia. Detailed functions of Ccdc85C protein have not been clarified. To reveal roles of Ccdc85C, we examined the distribution and expression pattern of Ccdc85C in the systemic developing organs in rats. Ccdc85C was expressed in various simple epithelia but not stratified epithelia. In the various epithelia, Ccdc85C was localized at cell-cell junctions and its expression was strong at apical junctions. Furthermore, intense expression was seen at developing period and gradually decreased with advancing development. Distribution of Ccdc85C coincides with that of proliferating epithelial cells. These results suggest that Ccdc85C plays an important role in the proliferative property of simple epithelia.
Open Access
Chronic a1-adrenoreceptor blockade produces age-dependent changes in rat thymus structure and thymocyte differentiation
(Murcia : F. Hernández, 2005) Plecas-Soloravic, B.; Hristic-Zivkovic, I.; Radojevic, K.; Kosec, D.; Leposavic, G.
In order to examine the influence of chronic a1-adrenergic receptor (a1-AR) blockade on the thymus structure and T-cell maturation, peripubertal and adult male rats were treated with urapidil (0.20 mg/kg BW/d; s.c.) over 15 consecutive days. Thymic structure and phenotypic characteristics of the thymocytes were assessed by stereological and flow cytometry analysis, respectively. In immature rats, treatment with urapidil reduced the body weight gain and, affecting the volume of cortical compartment and its cellularity decreased the organ size and the total number of thymocytes compared to age-matched saline-injected controls. The percentage of CD4+8- single positive (SP) thymocytes was decreased, while that of CD4-8+ was increased suggesting, most likely, a disregulation in final steps of the positively selected cells maturation. However, a1- AR blockade in adult rats increased the thymus weight as a consequence of increase in the cortical size and cellularity. The increased percentage of most immature CD4-8- double negative (DN) cells associated with decreased percentage of immature CD4+8+ double positive (DP) thymocytes suggests a decelerated transition from DN to DP stage of T-cell development. As in immature rats, the treatment in adult rats evoked changes in the relative numbers of SP cells, but contrary to immature animals, favoring the maturation of CD4+8- over CD4-8+ thymocytes. These results demonstrate that: i) chronic blockade of a1-ARs affects both the thymus structure and thymocyte differentiation, ii) these effects are age-dependent, pointing out to pharmacological manipulation of a1-AR-mediated signaling as potential means for modulation of the intrathymic T-cell maturation.
Open Access
Chronic hypoxia induced ultrastructural changes in the rat adrenal zona glomerulosa
(Murcia : F. Hernández, 2002) Lorente, M.; Mirapeix, R.M.; Miguel, M.; Longmei, W.; Volk, D.; Cervós-Navarro, J.
The adrenal cortex plays an important role in adaptation to various forms of stress, including hypoxia. While physiological changes in the aldosterone metabolism during hypoxia have been extensively described, few studies have focused on the morphological changes in the adrenal glands under chronic hypoxia. We studied the ultrastructure of the z o n a g l o m e ru l o s a of 6-month-old Wistar rats exposed to chronic normobaric hypoxia. Animals were divided into two groups: control (n=12) and hypoxic (n=12). In this latter group, the animals were kept at 7% O2 concentration after a gradual adaptation (21, 15, 12, 10, 8, 7 vol% O2 ). The duration of the study was 112 days. In comparison with normoxic rats, body weight and adrenal gland weight of hypoxic animals was significantly reduced by 18.5% (p=0.006) and 14.7% (p=0.001) respectively. The thickness of the z o n a glomerulosa decreased due to atrophy of cells. The main ultrastructural changes observed were: 1) a decrease in, or complete elimination of, lipid droplet content; 2) a marked increase in lysosome number; and 3) the presence of giant mitochondria. Our findings show that rats fail to adapt to severe chronic hypoxia. The ultrastructural changes in the zona g l o m e ru l o s a found in the present study could reflect changes in the aldosterone pathway.
Open Access
Early embryonic development in the rat following in utero exposure to alcohol and caffeine
(Murcia : F. Hernández, 1986) Ross, C.P.; Persaud, T.V.N.
The influence of both alcohol and caffeine on early embryonic development was investigated in pregnant rats. Compared to the corresponding controls, a high incidence of resorptions and abnormal embryos was induced following treatment of the animals with alcohol (0.015 ml/g body weight, 12.5% v/v, ¡.p.) on gestational days 6 through 12 and with caffeine (25 mg/kg body weight, ¡.v.) on gestational day 10. In addition, embryonic growth was severely affected. Reduction of placental blood circulation and impairment of cellular proliferation may account for the observed deleterious effects on the embryo.
Open Access
Effects of neurotensin and bombesin on the secretory and proliferative activity of regenerating rat adrenal cortex
(Murcia : F. Hernández, 1999) Hochol, A.; Markowska, A.; Meneghelli, V.; Jedrzejczak, N.; Majchrzak, M.; Nowak, M.; Nussdorfer, G.G.; Malendowicz, L.K.
Neurotensin (NT) and bombesin (BM)-like peptides are known to be involved in the regulation of the rat hypothalamo-pituitary-adrenal axis. By using selective NT- and BM-receptor antagonists (NT-A and BM-A, respectively) we investigated whether endogenous NT and BM-like peptides play a role in the control of rat adrenal secretion and growth during enucleation-induced regeneration. At day 5 of regeneration, NT-A did not affect the plasma concentrations of aldosterone (PAC) and corticosterone (PBC), but at day 8, it raised both PAC and PBC over the respective baseline value; the simultaneous administration of NT abolished this effect of NT-A. BMA did not alter PAC and PBC at day 5 of regeneration, while at day 8 it enhanced PBC, an effect reversed by BM. NT-A did not alter mitotic index, and BM-A lowered it at both day 5 and day 8 of regeneration, an effect suppressed by the simultaneous administration of BM. Collectively, these findings allow us to draw the following conclusions: 1) endogenous NT and BM-like peptides influence adrenocortical regeneration in rats; 2) NT exerts a tonic inhibitory action on both aldosterone and corticosterone secretion, without affecting cellproliferation rate; and 3) BM-like peptides exert a tonic suppressive effect on corticosterone production, coupled with a clear-cut stimulating effect on cell proliferation.
Open Access
Expression of major histocompatibility complex antigens and CR3 complement receptors in activated microglia following an injection of ricin into the sciatic nerve in rats
(Murcia : F. Hernández, 1992) Ling, E. A.; Kaur, C.; Wong, W. C.
The ventral horn motor neurons in the lower lumbar cord underwent rapid degeneration following an injection of Ricinus communis agglutinin- 60 (RCA) into the sciatic nerve. The cell death which was most drastic between the fifth and seventh postinjection day elicited a significant increase in the number of microglia. The activated microglia were scattered throughout the neuropil but the dramatic feature was their close association with the somata of the degenerating neurons. Often several microglial cells were seen surrounding the soma of a degenerating neuron. Immunocytochemical study showed that both the interstitial as well as the perineuronal activated microglia were labelled with the monoclonal antibodies OX-18 and OX-42 for the detection of MHCI encoded antigen and type three complement receptors, respectively. Intense immunoreactivity was observed especially in the perineuronal microglia with OX-18. Electron microscopic study confirmed the identification of the activated microglia. Although the activated microglia closely apposed the neuronal soma, there was no sign of a direct endocytosis. The cytoplasm of the activated microglia, however, contained massive lipofuscin bodies in longer survival animals. Electron microscopic immunocytochemical study showed that the immunoreactivity of the activated microglia was localized along their plasma membrane facing the neuronal soma. Since the microglia cells on the contralateral side of the ventral horn were not marked by the antibodies used, it was postulated that the vigorous expression of MHCI antigen and CR3 receptors on the activated microglia was induced by the neuronal degeneration resulting from the application of the toxin ricin.
Open Access
Expression of ribosomal protein L4 (rpL4) during neurogenesis and 5-azacytidine, (5AzC)-induced apoptotic process in the rat
(Murcia : F. Hernández, 2002) Ueno, M.; Nakayama, Hiroyuki; Kajikawa, S.; Katayama, K.; Suzuki, K.; Doi, K.
5-Azacytidine (5AzC) induces neuronal apoptosis in rat and mouse fetuses. 5AzC also induces apoptosis in undifferentiated PC12 cells, and ribosomal protein L4 (rpL4) mRNA expression increases prior to apoptosis. To clarify the roles of rpL4 during neurogenesis, we first examined the distribution of rpL4 mRNA in the developing rat brain by in situ hybridization and RT-PCR, and compared the results to the distribution of TUNEL- or PCNA-positive cells. rpL4 mRNA expression was strong in the ventricular zone (VZ), subventricular zone (SVZ), cortical plate (CP), cerebral cortex, granule cell layer (GCL), pyramidal cell layer (Py) and external granular layer (EGL) during embryonic and early postnatal days, and it was remarkably weakened thereafter. A lot of PCNApositive cells were observed in VZ, SVZ, and EGL during embryonic and early postnatal days, and such distribution of PCNA-positive cells was almost identical to rpL4 mRNA distribution. Only few TUNEL-positive cells were observed in VZ, SVZ, cerebral cortex, EGL, and hippocampus during embryonic and early postnatal days, and the regions with TUNEL-positive cells were not identical to rpL4 mRNA distribution. Next, the changes of rpL4 mRNA expression in the brain of 5AzC-treated rat fetuses were examined by in situ hybridization and RT-PCR. Apoptotic cells appeared at 9 to 24 hours after treatment (HAT). However, the rpL4 mRNA expression was unchanged during the apoptotic process. From the results, it is suggested that rpL4 would have certain roles in cell proliferation and differentiation during neurogenesis, but have no roles in 5AzC-induced apoptosis in the fetal brain.
Open Access
Ghrelin and adipose-derived mesenchymal stromal cells improve nerve regeneration in a rat model of epsilon-caprolactone conduit reconstruction
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2017) Hernández Cortés, Pedro; Toledo Romero, Miguel Angel; Delgado, Mario; Gonzalez Rey, Elena; Gómez Sánchez, Rafael; Prados Olleta, Nicolás; Aneiros Fernández, José; Crespo Lora, Vicente; Aguilar, Mariano; Galindo Moreno, Pablo; O’Valle, Francisco
Objective. Attempts have been made to improve nerve conduits in peripheral nerve reconstruction. We investigated the potential therapeutic effect of adipose-derived mesenchymal cells (ASCs) and ghrelin (GHR), a neuropeptide with neuroprotective, trophic, and developmental regulatory actions, on peripheral nerve regeneration in a model of severe nerve injury repaired with nerve conduits. Material and methods. The right sciatic nerves of 24 male Wistar rats were 10-mm transected unilaterally and repaired with Dl-lactic-ε-caprolactone conduits. Rats were then treated locally with saline, ASCs, or GHR. At 12 weeks post-surgery, we assessed limb function by measuring ankle stance angle and percentage muscle mass reduction and evaluated the histopathology, immunohistochemistry, ultrastructure, and morphometry of myelinated fibers. Main Results. Rats receiving GHR or ASCs showed no significant increased functional recovery in ankle stance angle (p=0.372) but a higher nerve area (p=0.015), myelin area (p=0.046) and number of myelinated fibers (p=0.012) in the middle and distal segments of operated sciatic nerves in comparison to saline-treated control animals. Conclusion. These results suggest that utilization of ghrelin or ASCs may improve nerve regeneration using Dl-lactic-ε-caprolactone conduits.
Open Access
Goodpasture's syndrome in ageing. An experimental study on the rat. I
(Murcia : F. Hernández, 1993) Escolar Castellón, J.de D.; Mateos, J.; Alfaro, E.; Escolar, M.A.; Miñana Amada, C.; Roche, P.
The following hypothesis is proposed: Experimental lung disease in old rats is different from this disease in adult rats. In order to demonstrate this, we performed a morphometrical evaluation of the pulmonary state of two groups of rats at different ages and to which Goodpasture's syndrome had been induced. 115 Wistar rats were used. They were divided into four different groups as follows: 1) Healthy adult rats which had not been subjected to treatment; 2) diseased adult rats to which antipulmonary serum had been administered; 3) healthy old rats; and 4) diseased old rats. With the help of a computerized system, the length of the alveolar chord, the thickness of the alveolar wall and the surface of the bronchial-associated lymphoid tissue in each group was calculated. We also counted the number of alveolar macrophages (AM) with haemosiderin, the percentage of goblet bronchial cells and that of AM, lymphocytes and polymorphonuclear leukocytes of the broncho-alveolar lavage (BAL). The following results were obtained. When related to the diseased adult rats, the diseased old rats showed an increase in the alveolar chord and a decrease in the thickness of the alveolar wall, as well as in the number of AM with haemosiderin, globet cells and BAL lymphocytes. These results support the proposed hypotheses, since the diseased adult animals showed signs of alveolar inflammation with interstitial edema, while in the diseased old animals these results are compatible with emphysema.
Open Access
Goodpasture's syndrome in ageing. An experimental study on the rat. II
(Murcia : F. Hernández, 1993) Escolar Castellón, J.de D.; Mateos, J.; Alfaro, E.; Escolar, M.A.; Miñana Amada, C.; Roche, P.
The following hypothesis is suggested: if a lung disease is induced in an adult rat, then its lung, in the senile age, will be different from what is considered to be a normal senile lung. In order to demonstrate this, the pulmonary state of two groups of old rats, one of which had suffered from Goodpasture's syndrome in the adult age has been assessed morphometrically. Fifty-three Wistar rats were used. They were divided into two groups: 1) healthy old rats; and 2) diseased old rats. Antipulmonary serum was administered to the latter and they were sacrificed a year later. Making use of a computing system, we calculated the following data for each group: the alveolar chord length, the alveolar wall thickness and the surface of the bronchial-associated lymphoid tissue (BALT). The alveolar macrophages (AM) with haemosiderin which were found in the lung tissue were also counted and the percentage of goblet bronchial cells and that of bronchoalveolar lavage (BAL) cells was also assessed. From the results, the following points should be emphasized: in diseased old rats, an increase in the alveolar chord, a decrease in lymphocytes with an increase in the AM of the BAL, and a decrease in goblet cells and AM with haemosiderin occur, al1 of which are significant when these rats are compared to healthy old rats. From this experiment it can be inferred that the lungs of the diseased old rats are morphologically different from those of the healthy old rats; the findings cannot be related to an inflammatory process.
Open Access
Growth pattern of experimental glioblastoma
(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2020) Ahlstedt, Jonatan; Förnvik, Karolina; Helms, Gunther; Salford, Leif G.; Ceberg, Crister; Skagerberg, Gunnar; Redebrandt, Henrietta Nittby
Glioblastoma multiforme (GBM) is an aggressive primary brain malignancy with a very poor prognosis. Researchers employ animal models to develop potential therapies. It is important that these models have clinical relevance. This means that old models, propagated for decades in cultures, should be questioned. Parameters to be evaluated include whether animals are immune competent or not, the infiltrative growth pattern of the tumor, tumor volume resulting in symptoms and growth rate. We here describe the growth pattern of an experimental glioblastoma model in detail with GFP positive glioblastoma cells in fully immune competent animals and study tumor growth rate and tumor mass as a function of time from inoculation. We were able to correlate findings made with classical immunohistochemistry and MR findings. The tumor growth rate was fitted by a Gompertz function. The model predicted the time until onset of symptoms for 5000 inoculated cells to 18.7±0.4 days, and the tumor mass at days 10 and 14, which are commonly used as the start of treatment in therapeutic studies, were 5.97±0.62 mg and 29.1±3.0 mg, respectively. We want to raise the question regarding the clinical relevance of the outline of glioblastoma experiments, where treatment is often initiated at a very early stage. The approach presented here could potentially be modified to gain information also from other tumor models.
Open Access
Histologic evaluation of the effect of grape seed oil and ferric sulfate in pulpotomy applied to molar teeth of rats: An in vivo study
(2026) Günay Yapici Yavuz; Ebru Elibol Annaç; Aydın Keskinrüzgar; Muhammed Baybatmaz; İlknur Öz; Mesut Tozar; Osman Küçükkelepçe; Kamile Nur Tozar; Biología Celular e Histología; Universidad de Murcia, Departamento de Biologia Celular e Histiologia
Background. The objective of this study was to examine the healing potential of Grape Seed Oil (GSO) on the pulp tissue that remains following pulpotomy treatment. Materials and Methods. The upper first molars of 18 two-month-old male Wistar albino rats were divided into two groups according to the material used in pulpotomy treatment. In the pulpotomy treatment group, GSO was used, while ferric sulfate (FS) was used in the control group. The rats were euthanized at 24 hours, 15 days, and 30 days following treatment. Histopathological evaluation of the samples was conducted using the hematoxylin-eosin staining method. The evaluation was conducted to ascertain alterations in connective tissue, vascular changes (i.e., angiopathic findings), inflammation, and hemorrhagic findings in the pulp. The data obtained in this study were analyzed with the IBM SPSS Statistics Version 21 software program. Results. In the present study, it was observed that the inflammatory response in the GSO group was higher than that in the FS group at 24 hours. The investigation revealed that the vascular response exhibited a higher magnitude in the GSO group compared to the FS group at 24 hours and at day 15. However, this response exhibited a decline at day 30. Despite an increase in hemorrhaging on the 15th day in the GSO group, this phenomenon decreased over time. Conclusions. It has been observed that GSO is a biocompatible material that can be used as an alternative to FS in pulpotomy treatment.
Open Access
Histopathological and biochemical changes in rat thyroid following acute exposure to hexavalent chromium
(Murcia : F. Hernández, 2010) Mahmood, Tariq; Zia Quresh, Irfan; Javed Iqbal, Muhammad
Chromium in hexavalent form is highly toxic and a known carcinogen, although its effects on thyroid structure and function are relatively unexplored. Workers in an industrial environment can be, at times, exposed to this form of chromium. The present study was, therefore, designed using laboratory rats as a model system to investigate the effect on thyroid structure and function following two acute intraperitoneal doses of 30 mg/kg b.w. potassium dichromate administered within 48 hours. The results showed that hypothalamic chromium concentration increased (p<0.05) while thyroid chromium concentration decreased (p<0.01).The excretion of chromium in urine increased (p<0.05). The treated thyroid sections revealed hyperplasia. Follicles were disorganized, clustered and collapsed, while some of them were fused. Interfollicular spaces widened. Morphometrical analysis showed significantly (p<0.001) increased number of follicles whereas the follicular size significantly decreased (p<0.001). Nuclei were regressed (p<0.001); nuclear shapes were irregular; round, oval and shrunken. The membrane on the apical as well as the basal lamina side showed disruption. Colloid retraction within the follicles was noticeable in some sections stained with Periodic acid Schiff (PAS). Serum free tetra-iodothyronine (FT4) and free tri-iodothyronine (FT3) levels decreased (p<0.01 and p<0.001, respectively), while serum thyroid stimulating hormone (TSH) concentration increased (p<0.01). Ultrastructural analysis showed disrupted basal laminae of the follicles, regressed nuclei and disrupted cell organelles. Acridine orange stained thyroid cells demonstrated excessive dead cells, whereas DNA fragmentation assay demonstrated percent decrease of hypothalamic, pituitary and thyroidal total DNA.
Open Access
Histopathological, immunohistochemical, and stereological analysis of the effect of Ginkgo biloba (Egb761) on the hippocampus of rats exposed to long-term cellphone radiation
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Gevrek, Fikret
Cellular phones are major sources of electromagnetic radiation (EMR) that can penetrate the human body and pose serious health hazards. The increasingly widespread use of mobile communication systems has raised concerns about the effects of cellphone radiofrequency (RF) on the hippocampus because of its close proximity to radiation during cellphone use. The effects of cellphone EMR exposure on the hippocampus of rats and the possible counteractive effects of Ginkgo biloba (Egb761) were aimed to investigate. Rats were divided into three groups: Control, EMR, and EMR+Egb761. The EMR and EMR+Egb761 groups were exposed to cellphone EMR for one month. Egb761 was also administered to the EMR+Egb761 group. Specifically, we evaluated the effect of RF exposure on rat hippocampi at harmful EMR levels (0.96 W/kg specific absorption rate [SAR]) for one month and also investigated the possible impact of Egb761 using stereological, TUNEL-staining, and immunohistochemical methods. An increase in apoptotic proteins (Bax, Acas-3) and a decrease in anti-apoptotic protein (Bcl-2) immuno-reactivity along with a decrease in the total granule and pyramidal cell count were noted in the EMR group. A decrease in Bax and Acas-3 and an increase in Bcl-2 immunoreactivity were observed in rats treated with Egb761 in addition to a decrease in TUNEL-stained apoptotic cells and a higher total viable cell number. In conclusion, chronic cellphone EMR exposure may affect hippocampal cell viability, and Egb761 may be used to mitigate some of the deleterious effects.