DigitalUM :: Browsing by Subject "Rats"

Browsing by Subject "Rats"

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Open Access
Birth defects in juvenile Wistar rats after exposure to immunosuppressive drugs during pregnancy
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2017) Kabat Koperska, Joanna; Kolasa Wołosiuk, Agnieszka; Pilutin, Anna; Safranow, Krzysztof; Kosik Bogacka, Danuta; Baranowska Bosiacka, Irena; Gołembiewska, Edyta; Kędzierska, Karolina; Domański, Leszek; Ciechanowski, Kazimierz
Introduction: Immunosuppressive drugs and their active metabolites can cross the placental barrier and enter fetal circulation. The adverse effects on the fetus include chromosomal aberrations, structural malformations, organ-specific toxicity and intrauterine growth retardation. The aim of our study was to investigate the impact of “safe” and “contraindicated” immunosuppressive drugs on birth defects in juvenile Wistar rats after exposure of pregnant female rats to these drugs. Material and methods: The study was conducted on 32 female Wistar rats, subjected to immunosuppressive regimens most commonly used in therapy of human kidney transplant recipients. The animals received drugs by oral gavage 2 weeks before pregnancy and during 3 weeks of pregnancy. Results: Treatment with mycophenolate mofetil and everolimus turned out to be toxic. We have noticed a significantly reduced number of live births in all pregnant rats exposed to these drugs in combination with calcineurin inhibitors and prednisone. Malformations and histological changes of fetal organs were confirmed after mycophenolate mofetil exposure during pregnancy. Conclusions: Mycophenolate mofetil turned out to be more toxic when used with tacrolimus than with cyclosporin (delivery of live offspring was possible only in the latter group). Everolimus in combination with cyclosporin effectively suppressed the fetal maturation in utero, but did not contribute to the development of malformations.
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Bone union formation in the rat mandibular symphysis using hydroxyapatite with or without simvastatin: effects on healthy, diabetic, and osteoporotic rats
(Springer Heidelberg, 2020-01-11) Camacho Alonso, Fabio; Martínez Ortiz, C.; Plazas Buendía, L.; Mercado Díaz, A.M.; Vilaplana Vivo, C.; Merino, J.J:; Martínez Beneyto, Yolanda; Navarro Cámara, José Antonio; Buendía Marín, Antonio Julián; Dermatología, Estomatología, Radiología y Medicina Física
Objective The objective is to compare new bone formation in critical defects in healthy, diabetic, and osteoporotic rats filled with hydroxyapatite (HA) alone and HA combined with simvastatin (SV). Materials and methods A total of 48 adult female Sprague-Dawley rats were randomized into three groups (n = 16 per group): Group, 1 healthy; Group 2, diabetics; and Group 3, osteoporotics. Streptozotocin was used to induce type 1 diabetes in Group 2, while bilateral ovariectomy was used to induce osteoporosis in Group 3. The central portion of the rat mandibular symphysis was used as a physiological critical bone defect. In each group, eight defects were filled with HA alone and eightwithHA combined with SV. The animals were sacrificed at 4 and 8 weeks, and the mandibles were processed for micro-computed tomography to analyze radiological union and bone mineral density (BMD); histological analysis of the bone union; and immunohistochemical analysis, which included immunoreactivity of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP-2). Results In all groups (healthy, diabetics, and osteoporotics), the defects filled with HA+ SV presented greater radiological bone union, BMD, histological bone union, and more VEGF and BMP-2 positivity, in comparison with bone defects treated with HA alone. Conclusions Combined application ofHAand SVimproves bone regeneration in mandibular critical bone defects compared with application of HA alone in healthy, diabetic, and osteoporotic rats. Clinical relevance This studymight help to patients with osteoporosis or uncontrolled diabetes type 1, but future studies should be done.
Open Access
Changes of calcium/calmodulin-dependent protein kinase II expression in dorsal root ganglia during maturation in long-term diabetes
(F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2014) Ferhatovic, Lejla; Jelicic Kadic, Antonia; Boric, Matija; Puljak, Livia
Calcium/calmodulin-dependent protein kinase II (CaMKII) is considered one of the key intracellular signaling proteins for development of neuropathy. We analyzed the expression of total CaMKII (tCaMKII) and its alpha, beta, gamma and delta isoforms in dorsal root ganglia (DRG) in a rat model of Diabetes mellitus type I (DM1), 6 months and 1 year after diabetes induction. Diabetes was induced with streptozotocin and confirmed by measuring glucose levels and weight increase. Immunohistochemistry was performed for detection of tCaMKII and its isoforms in L4 and L5 DRGs. A significant decrease of CaMKII alpha and beta isoforms was noted 6 months after diabetes induction, while CaMKII gamma and delta were significantly decreased after 12 months in diabetic rats compared to controls. Analysis of neuronal subgroups based on the neuronal diameter revealed that the expression of alpha, beta and delta isoforms decreased only in small-diameter neurons. In conclusion, a significant decrease of specific CaMKII isoforms in small-diameter DRG neurons may suggest involvement of CaMKII alpha, beta and delta in the development of complex events responsible for the development of neuropathy in long-term diabetes during maturation. CaMKII is a part of the neuronal pathway that regulates the firing properties of excitable cells, especially neurons, and decreased CaMKII activity may be responsible for generation of aberrant signals, hyperalgesia and neuropathic pain.
Open Access
Characterization of diet based nonalcoholic fatty liver disease/nonalcoholic steatohepatitis in rodent models: Histological and biochemical outcomes
(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2022) Akbari, Ghaidafeh; Mard, Seyyed Ali; Savari, Feryal; Barati, Barat; Sameri, Maryam Jafar
Nonalcoholic fatty liver disease (NAFLD), as the most common chronic liver disease, is rapidly increasing worldwide. This complex disorder can include simple liver steatosis to more serious stages of nonalcoholic fibrosis and steatohepatitis (NASH). One of the critical concerns in NASH research is selecting and confiding in relying on preclinical animal models and experimental methods that can accurately reflect the situation in human NASH. Recently, creating nutritional models of NASH with a closer dietary pattern in human has been providing reliable, simple, and reproducible tools that hope to create a better landscape for showing the recapitulation of disease pathophysiology. This review focuses on recent research on rodent models (mice, rats, and hamsters) in the induction of the dietary model of NAFLD /NASH. This research tries to compile the different dietary compositions of NASH, time frames required for disease development, and their impact on liver histological features as well as metabolic parameters.
Open Access
Differences in neuromuscular junctions between intrinsic muscles of the forepaw and biceps muscles in rats
(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2024) Qiao, Jing; Gu, Jing Yu; Li, Bo
Motor endplates of the interossei muscles become destabilized, whereas those of the biceps muscles remain stable in a rat model of obstetric brachial plexus palsy. However, it is unclear whether the morphology of the motor endplates of the interossei muscles is different from that of the biceps muscles in normal rat. We hypothesized that the motor endplates in the interossei muscles have specific characteristics different from those in the biceps muscles. The motor endplates were labeled with α-bungarotoxin and synaptophysin. The cross-sectional areas of the muscle fibers, the morphologies of the motor endplates, and the absolute and normalized areas (corrected by muscle fiber diameter) of the motor endplates of the interossei muscles and the biceps muscles were compared in rats at 1, 3, and 5 weeks after birth. The cross-sectional area of the interossei muscles and biceps muscle fibers were found to have increased gradually at 1, 3, and 5 weeks, but that of the biceps muscles was larger than that of the interossei muscles. The motor endplates of the interossei muscles and the biceps muscles gradually develop from crescent to pretzel shape after birth, and those of the interossei muscles have a smaller area. At 1, 3, and 5 weeks postnatally, the area of postnatal normalized motor endplates of the interossei muscles was much smaller than that of the biceps muscles. A better understanding of the morphological differences of the motor endplates between the interossei muscles and the biceps muscles may help to understand their physiological and pathological changes.
Open Access
Expression of activity-dependent neuroprotective protein in the brain of adult rats
(Murcia : F. Hernández, 2008) Gennet, N.; Herden, C.; Bubb, V.J.; Quinn, J.P.; Kipar, A.
Activity-dependent neuroprotective protein (ADNP) is a VIP-regulated gene, which is essential for brain development. A synthetic peptide (NAP) derived from the ADNP sequence is highly neuroprotective, therefore it has been hypothesised that ADNP has a similar role. ADNP contains classical transcription factor motifs and nuclear localisation domains, but it has also been reported to be secreted and to co-localise with microtubules, indicating that ADNP may have multiple functions. We investigated the pattern of ADNP expression by immunohistology in normal rat brain, in order to generate a framework for future studies examining changes in ADNP expression in response to noxious stimuli or in models of disease. We found widespread ADNP-like immunoreactivity in neurons throughout the rat brain, with the highest expression in the cerebellum, and strong expression in the thalamus, mesencephalon, pons and medulla oblongata. ADNPlike immunoreactivity was mainly observed in the cytoplasm of neurons, and fibre tracts were often strongly positive as well. In addition, positive neuronal nuclei were occasionally observed. ADNP-like immunoreactivity was lost in degenerating ‘dark’ neurons, the morphologically unaltered adjacent cells. Occasional astrocyte and microglial cells were also positive. We suggest that the widespread expression of ADNP may correlate with the wide-ranging protective effects of NAP, and that the cytoplasmic and axonal localisation of ADNP-like immunoreactivity suggests additional, nontranscriptional functions of ADNP
Open Access
Histological parameters of the adrenal cortex after testosterone application in a rat model of the andropause
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2016) Ajdžanović, Vladimir Z.; Jarić, Ivana M.; Živanović, Jasmina B.; Filipović, Branko R.; Šošić Jurjević, Branka T.; Ristić, Nataša M.; Stanković, Sanja D.
Histological analysis of the adrenal cortex, after testosterone application in a rat model of the andropause, was the main subject of the present study. Middle-aged Wistar rats were divided into shamoperated (SO; n=8), orchidectomized (Orx; n=8) and testosterone treated orchidectomized (Orx+T; n=8) groups. Testosterone propionate (5 mg/kg b.m. /day) was administered for three weeks, while SO and Orx groups received the vehicle alone. Histological objectives were achieved using stereology, histochemistry and steroid receptor immunostaining. The concentrations of testosterone, aldosterone, corticosterone and DHEA were determined by immunoassays. Expectedly, increased (p<0.05) serum concentration of testosterone was observed in Orx+T group. The volume of ZG cells and nuclei increased in Orx+T animals by 50% and 25% (p<0.05) respectively, but the serum concentrations of aldosterone decreased (p<0.05) by 60%, all compared to the same parameters in Orx group. The immunostaining for androgen receptors (ARs) suggested their cytoplasmic localization in ZG cells of Orx+T rats. Volume of the ZF cell nuclei in Orx+T group decreased (p<0.05) by 17%, which was followed by the significant (p<0.05) fall in corticosterone production and secretion, all in comparison with Orx animals. Also, nuclear immunolocalization of ARs of high optical density was observed through the ZF of Orx+T group. In Orx+T rats volume of ZR cells and nuclei, and circulating DHEA concentration increased (p<0.05) by 68%, 22% and about 6.6 times respectively, compared to Orx animals. Besides the extra-receptor actions in adrenal cortex, testosterone supposedly affects some steroidogenesisrelated gene expression, as indicated by centripetal rise in the number of nuclear ARs.
Open Access
Immunostaining of proinflammatory cytokines in renal cortex and medulla of rats exposed to gold nanoparticles
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2017) Khan, Haseeb A.; Ibrahim, Khalid E.; Khan, Ayaat; Alrokayan, Salman H.; Alhomida, Abdullah S.
Recently, gold nanoparticles (GNPs) have shown promising applications in targeted drug delivery and contrast imaging. Although in vitro cytotoxicity of GNPs has been thoroughly studied, there are limited data on in vivo toxicity of GNPs. In this study, we evaluated the effects of intraperitoneally injected 10 nm and 50 nm GNPs (5 µg/animal) on the expression of proinflammatory cytokines (IL-1β, IL-6 and TNF-α) on day 1 and day 5, post-exposure. The results of immunohistochemistry showed that both 10 nm and 50 nm GNPs induced an acute phase expression of proinflammatory cytokines in renal cortex and medulla. This proinflammatory response was comparatively more intense in renal medulla than cortex. All the three cytokines were undetectable in control cortex and medulla. In conclusion, both 10 nm and 50 nm GNPs caused an acute phase induction of proinflammatory cytokines in cortex and medulla of rat kidneys. An intense immunostaining of proinflammatory cytokines in renal medulla warrants further studies to evaluate the nephrotoxicity of GNPs to validate the safe application of GNPs for contrast imaging in renal insufficiency.
Open Access
In vitro and in vivo efficacy evaluation of new self-assembling curcumin loaded nanohyaluronan-glycerosomes on wound restoring in health and diabetic rats
(Elsevier, ) Gómez García, Francisco José; Ramírez Andreo, Antonio; Manconi, María; Manca, María Letizia; Matricardi, Pietro; Di Meo, Chiara; Fernàndez-Busquets, Xavier; Martínez Díaz, Francisco; Salmerón Martínez, Diego; López Jornet, Pía; Ciencias Sociosanitarias
In this study the wound healing efficacy of new self-assembling curcumin loaded nanohyaluronan-glycerosomes has been tested in healthy and diabetic rats. Curcumin was loaded in nanohyaluronan-liposomes and -glycerosomes, special vesicles obtained mixing curcumin, hyaluronan nanohydrogel and soy lecithin. Curcumin loaded liposomes and glycerosomes were also prepared, characterized and tested as references. The physico-chemical (size and size distribution, surface charge and morphology), and technological (entrapment efficiency, stability over time and skin delivery) characteristics and biological performances (safety, ability to protect in vitro cells from oxidative damage) of prepared formulations were measured. Finally, they were daily applied to skin wounds of healthy or diabetic rats. The animal skin was excided and analysed at days 3, 7 and 14. The macroscopic observation underlined the higher ability of curcumin loaded nanohyaluronan-glycerosomes to improve wound healing in diabetic rats, already on day 3 up to day 14 (p < 0.05). Histopathological analysis confirmed an accelerated re-epithelization in healthy rats, while increased angiogenesis in diabetic ones. The superior therapeutic efficacy of curcumin loaded nanohyaluronan-glycerosomes compared to other formulations can be related to their enhanced ability to deliver higher curcumin concentrations at the wound site due to a synergistic effect of glycerol, hyaluronan nanohydrogel and lecithin.
Open Access
Matrix production of smooth muscle cells from rat aorta in vitro
(Murcia : F. Hernández, 1993) Stieme, B.; Springmeier, G.; El-Jarad, L.; Schroter-Kermani, C.
Immunofluorescence microscopic methods served to demonstrate the production of the following matrix components in cultures of vascular smooth muscle cells from rat aorta: fibronectin; nidogen; heparan sulphate-proteoglycan (HS-PG); laminin; and collagen types 1, 111, IV, V, and VI. A time-dependence of synthesis and secretion could be shown for a number of components of the extracellular matrix (ECM), such as laminin. The results revealed the following estimated quantitative differences of the collagen types: type 1 > type 111 > types V and VI. A filamentouslfibrillar matrix and also occasionally a typical basal lamina could be demonstrated electron microscopically around the smooth muscle cells.
Open Access
Microglial reaction in focal cerebral ischaemia induced by intra-carotid homologous clot injection
(F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2001) Ng, Y.-K.; Ling, E.-A.
This study examined the microglial reaction in a simulated thrombo-embolus ischaemia in rats given an intracarotid injection of a suspension of homologous blood clot. All rats including the controls receiving vehicle injection were perfused at 5 hours, and 1, 3 and 7 days post-operation. The brains were removed and processed for immunohistochemistry using a panel of monoclonal antibodies: OX-42, OX-18 and OX-6 for labeling of microglia. In rats given saline injection OX42 immunoreactive microglial cells were observed to be distributed quite evenly throughout the whole brain. When injection of clot suspension was given, microglial cells responded vigorously, particularly in the ipsilateral hippocampus. Microglial reaction was also detected in the ipsilateral cerebral cortex, caudate as well as septal nuclei. The majority of the detected reactive microglial cells were hypertrophied showing thick or stout processes. Some rod-like and amoeboid microglia were also observed. Rarely did the reactive microglia express OX-6 immunoreactivity. All microglial cells were unreactive for OX-18. The actual mechanisms leading to the microglial activation as well as functions of reactive microglia in focal cerebral ischaemia remain speculative. In the absence of direct evidence, it could only be suggested that they may act as sensor cells for detection of subtle alterations in the microenvironment, probably in response to focal ischaemia and/or leakage of serumderived factors induced by thrombo-embolus stroke.
Open Access
Miringoplastia con membrana amniótica en un modelo murino de perforación timpánica cronificada
(Universidad de Murcia, 2022-07-29) Fages Cárceles, Nathalie; Esteban Sánchez, Tomás; Marín Atucha, Noemí; Escuela Internacional de Doctorado
Se denomina perforación timpánica a la solución de continuidad que tiene lugar en la membrana timpánica y puede producirse por múltiples posibles causas, siendo las más frecuentes las otitis medias agudas de repetición o las crónicas y los traumatismos. Por otro lado, se denomina miringoplastia al cierre quirúrgico de la perforación timpánica. Existen múltiples injertos descritos en la literatura para llevar a cabo el cierre de la perforación timpánica, sin prevalecer ninguno por encima del resto. Consideramos que la membrana amniótica podría ser un injerto idóneo para cerrar la perforación por sus propiedades antiinflamatorias y antibacterianas, por favorecer una adecuada epitelización e inhibición de la fibrosis, por su escasa inmunogenicidad y por su transparencia. El objetivo de este estudio es investigar la eficacia de los injertos de membrana amniótica en el tratamiento de las perforaciones timpánicas. Para ello, hemos diseñado un estudio preclínico prospectivo con 57 ratas Sprague Dawley a las que se les realizó una perforación timpánica y se les cronificó con mitomicina C y dexametasona. Posteriormente, se dividieron en dos grupos, 34 pertenecieron al grupo experimental donde la miringoplastia fue realizada con membrana amniótica y 23 pertenecieron al grupo control, en el cual la miringoplastia se realizó con cutanplast (esponja de material hemostásico). Como resultados, hemos obtenido un 14,7% de cierres en el grupo experimental y un 8,7% en el grupo control, sin diferencias estadísticamente significativas. Como conclusión, la membrana amniótica no ha resultado eficaz para el cierre de perforaciones timpánicas cronificadas previamente en el modelo murino con mitomicina C y dexametasona
Open Access
Morphological changes in the isolated rat liver perfused in a non-recirculating system, scanning and transmission electron microscopy
(Murcia : F. Hernández, 1987) Al-Ali, Saad Y.; Hassan, Ibrahim M.; Al-Zuhair, A.G.H.
Isolated perfused rat livers have been used for various studies, but detailed investigation into the structural integrity of hepatocytes of this system is lacking. In this study, isolated rat livers were perfused in vitro with oxygenated Krebs-Ringer bicarbonate buffer solution, for 2 minutes and l , 2,3, and 4 hour (S) at 37"C, using a non-recirculating perfusion system. The perfused livers were processed for semithin section light microscopy, transmission electron microscopy, and scanning electron microscopy. Sectional areas of cell deaths were measured by a camera-tracing assembly from 1.5 pm thick Araldite sections stained with toluidine blue. Progressive nuclear and cytoplasmic changes, leading to cell death, occurred in the hepatocytes of the centrilobular zone, during the 2nd, 3rd, and 4th hour of the perfusion at a rate of 9.03% ?IS%, 38.7% f2.7%, and55.1% f 5.9% (mean f standard deviation) of the total sectional areas respectively. Midzonal hepatocytes showed normal basophilic staining but exhibited loss of glycogen granules. loss of microvilli, development of aqueous vacuoles and formation of blebs. The fine structures of cell organelles, glycogen granules, microvilli and plasma membrane of the cells in the periportal zone were well preserved throughout the experimental period. For further quantitative, metabolic and functional studies using isolated rat liver perfused with Krebs-Ringer solution, it is evident from the present investigation tKat the periportal zone represents the functional region of the hepatic lobule. Whilst progressive changes, leading to cell death, occurred in the centrilobular zone.
Open Access
Oxidized regenerated cellulose does not prevent the formation of experimental postoperative perineural fibrosis assessed by digital analysis
(Murcia: F. Hernández, 2010) Hernández Cortés, Pedro; Peregrina, Magdalena; Aneiros Fernández, José; Tassi, Mohamed; Pajares López, Miguel; Toledo, Miguel; O’Valle, Francisco
Introduction: It is difficult to prevent and treat intra- and peri-neural fibrosis after peripheral nerve surgery. Many authors have attempted to develop and verify the effectiveness of substances to decrease the formation of adherences in different tissues. Material and Methods: this study aimed to assess the effectiveness of a barrier of oxidized regenerated cellulose (ORC) to reduce adherence and perineural fibrosis in a model of surgical perineural induced fibrosis in rat sciatic nerve in 40 rats. After tissue aggression, the nerve of the right rear limb was wrapped in ORC and the left limb served as control. Animals were killed at 3 and 6 weeks, and nerves and muscle mass were extracted en bloc. Connective tissue was quantified by conventional histopathological techniques and Fibrosis HR® automatic image analysis. Results: No significant differences were found in intra- or peri-neural induced fibrosis between control nerves (6.88% and 8.90%, respectively) and treated nerves (6.57% and 9.90%) at 3 or 6 weeks (10.41% and 12.51% in controls; 11.85% and 15.72% in treated nerves). Inflammatory phenomena and granulomatous reactions were more frequent in treated animals. Conclusions: ORC conferred no advantage in prevention of nerve fibrosis and might have interfered with healing.
Open Access
Potential influence of prenatal 2.45 GHz radiofrequency electromagnetic field exposure on Wistar albino rat testis
(Universidad de Murcia, Departamento de Biologia Celular e Histiologia, 2021) Almášiová, Viera; Holovská, Katarína; Andrašková, Sandra; Cigánková, Viera; Ševčíková, Zuzana; Raček, Adam; Andrejčáková, Zuzana; Tóth, Štefan; Tvrdá, Eva; Molnár, Ján; Račeková, Enikö
An ever-increasing use of wireless devices over the last decades has forced scientists to clarify their impact on living systems. Since prenatal development is highly sensitive to numerous noxious agents, including radiation, we focused on the assessment of potential adverse effects of microwave radiation (MR) on testicular development. Pregnant Wistar albino rats (3 months old, weighing 282±8 g) were exposed to pulsed MR at a frequency of 2.45 GHz, mean power density of 2.8 mW/cm2, and a specific absorption rate of 1.82 W/kg for 2 hours/day throughout pregnancy. Male offspring were no longer exposed to MR following birth. Samples of biological material were collected after reaching adulthood (75 days). In utero MR exposure caused degenerative changes in the testicular parenchyma of adult rats. The shape of the seminiferous tubules was irregular, germ cells were degenerated and often desquamated. The diameters of the seminiferous tubules and the height of the germinal epithelium were significantly decreased (both at **p<0.01), while the interstitial space was significantly increased (**p<0.01) when compared to the controls. In the group of rats prenatally exposed to MR, the somatic and germ cells were rich in vacuoles and their organelles were often altered. Necrotizing cells were more frequent and empty spaces between Sertoli cells and germ cells were observed. The Leydig cells contained more lipid droplets. An increased Fluoro Jade - C and superoxide dismutase 2 positivity was detected in the rats exposed to MR. Our results confirmed adverse effects of MR on testicular development.
Open Access
Prenatal and/or postnatal high-fat diet alters testicular parameters in adult Wistar Albino rats
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Campos Silva, Pamella; Costa, Waldemar S.; Sampaio, Francisco J.B.; Gregorio, Bianca M.
Here, we evaluated the effects of a high-fat diet during the prenatal and/or postnatal period on the metabolic parameters and testes of 4-month-old Wistar rats. The experimental groups, composed of male Wistar rats, were: C/C (n=8), HF/HF (n=8) (pups with the same diet as their dams, after weaning), C/HF (n=8), and HF/C (n=9) (pups with a different diet after weaning, from that of their dams). The biometric parameters, blood glucose levels, serum levels, the gonadosomatic index, sperm parameters, testes, and genital fat deposits were evaluated. The HDL-c serum levels were significantly lower in the C/HF group (P=0.0100), whereas animals in the HF/C group presented hypertriglyceridemia (P=0.0005). The sperm concentration was lower in the HF/HF group than in the HF/C group (P=0.0072), and sperm viability was lower in all groups receiving a high-fat diet (P<0.0001). The tubular compartment was the smallest in the HF/HF group (P<0.0001). The diameter of the seminiferous tubule was the widest in the HF/C group (P<0.0001). The height of the seminiferous epithelium in all groups was lower than that in the C/C group (P<0.0001). Testosterone and steroidogenic acute regulatory protein (STAR) expression levels were lower in the C/HF group (P=0.0218 and P=0.0215, respectively). The HF diet, regardless of the administration period, induced a limited number of metabolic changes, and modifications in the histoarchitecture of the testes and sperm parameters. These data suggest that a HF diet may cause disturbances in spermatogenesis and fertility impairment in adulthood.
Open Access
Soy isoflavone effects on the adrenal glands of orchidectomized adult male rats: a comprehensive histological and hormonal study
(Universidad de Murcia. Departamento de Biología Celular e Histología, 2018) Milošević, Verica Lj.; Severs, Walter B.; Ristić, Nataša M.; Manojlović Stojanoski, Milica N.; Popovska Perčinić, Florina V.; Šošić Jurjević, Branka T.; Pendovski, Lazo B.; Trifunović, Svetlana L.; Miler, Marko Š.; Ajdžanović, Vladimir Z.
Genistein (G) and related soy phytoestrogens have been studied for potential usefulness in different chronic diseases, and may ameliorate signs of aging. They have a profound influence on the hypothalamopituitary-adrenal (HPA) axis. The present study utilized the rat model of mild andropause to thoroughly evaluate the effects of G and soy extract on the adrenal gland and related blood hormones. Adult male rats were orchidectomized (Orx) or sham operated (SO). Orx rats received daily subcutaneous injections for 3 weeks of solvent, or G (Orx+G, 30 mg/kg), or commercial soy extract (Orx+Soy, 30 mg/kg). Adrenal glands and blood were harvested at the end of the treatment for hormone analyses, histology and design-based stereology. Compared to SO rats Orx evoked significant (P<0.05) changes including: the replicating cell number in the 3 adrenocortical zones; vascularity and cortical volume and blood levels of adrenocorticotropic hormone (ACTH), aldosterone and dehydroepiandrosterone (DHEA). When comparing Orx vs. Orx+G groups the following significant (P<0.05) changes were observed: a further increase in number of replicating cells in zonas glomerulosa and reticularis, vasculature network presence, cortical and zona reticularis volumes, ACTH and corticosterone concentrations, and lower DHEA levels. Comparing Orx vs. Orx+Soy resulted in elevated (P<0.05) ACTH and corticosterone levels. Structural integrity of the adrenal gland was unchanged vs. SO rats. Overall, G and soy extract treatments resulted in proliferative activity and/or vasculature support in the adrenal cortex. The data and current literature support the impression of a beneficial effect of soy components on the homeostatic response to stress.
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Studying the effects of multiple invasive mammals on Cory’s shearwater nest survival
(Springer, 2012-07-06) Hervías Parejo, Sandra; Henriques, A.; Oliveira, N.; Pipa, Tania; Cowen, H.; Ramos, Jaime A.; Nogales, Manuel; Geraldes, P.; Silva, C.; Ruiz de Ybáñez Carnero, María del Rocío; Oppel, S.; Sanidad Animal
The most common invasive mammals— mice, rats, and cats—have been introduced to islands around the world, where they continue to negatively affect native biodiversity. The eradication of those invasive mammals has had positive effects on many species of seabirds. However, the removal of one invasive mammal species may result in abundance changes of other species due to trophic and competitive interactions among species. Understanding the overall impact of several invasive species is a key challenge when evaluating the possible effects of eradication programmes. Here we assess the influence of the three most common invasive mammals on nest survival of Cory’s shearwater (Calonectris diomedea). We monitored six breeding colonies over 3 years and measured the activity of mice, rats and cats to examine the influence of invasive mammals on nest survival. We found that nest survival showed a similar temporal trend in all years, with lowest weekly survival probabilities shortly after chicks hatched. Cats were identified as major predators of chicks, but no measure of colony-specific cat activity was able to adequately explain variation in shearwater nest survival. Nest survival was on average 0.38 (95 % confidence interval 0.20–0.53) and varied among colonies as well as over time. We found a small positive influence of rats on nest survival, which may indicate that the presence of small rodents as alternative prey may reduce cat predation of chicks. Our findings suggest that the eradication of rodents alone may exacerbate the adverse effects of cats on shearwater nest survival.
Open Access
Submucosal plexus of terminal ileum: a study of the cholinergic and noradrenergic nerves in rats with streptozotocin-induced diabetes
(Murcia : F. Hernández, 1992) Morte, L.; Cuervas-Mons, M.; Junquera, C.; Ramón y Cajal, S.
-In order to study the type and degree of the alterations in the innervation of the intestine in experimental diabetes, a histochemical study on the cholinergic and noradrenergic nerves of the submucosal plexus of terminal ileum from rats with streptozotocin-induced diabetes was performed. The results obtained suggest that the diabetic animals keep the cholinergic activity undamaged 20 weeks after the induction of the illness, while the number of the catecholaminergic nerves appears to be markedly reduced.
Open Access
Vasoconstrictor and Pressor Effects of Des-Aspartate-Angiotensin I in Rat.
(2022-05-22) Garcia-estañ Lopez, J. M.; Wangensteen,Rosemary; Gómez-Guzmán, Manuel; Banegas, Inmaculada; Rodríguez-Gómez, Isabel; Jiménez, Rosario; Vargas,Félix; Duarte, Juan; Fisiología
This study investigated the vasoactive effects of des-aspartate-angiotensin-I (DAA-I) in male Wistar rats on whole body vascular bed, isolated perfused kidneys, and aortic rings. Dose– response curves to DAA-I were compared with those to angiotensin II (Ang II). The Ang II-type-1 (AT1) receptor blocker, losartan, was used to evaluate the role of AT1 receptors in the responses to DAA-I. Studies were also conducted of the responsiveness in aortic rings after endotheliumremoval, nitric oxide synthase inhibition, or AT2 receptor blockade. DAA-I induced a dose-related systemic pressor response that was shifted to the right compared with Ang II. Losartan markedly attenuated the responsiveness to DAA-I. DAA-I showed a similar pattern in renal vasculature and aortic rings. In aortic rings, removal of endothelium and nitric oxide inhibition increased the sensitivity and maximal response to DAA-I and Ang II. AT2 receptor blockade did not significantly affect the responsiveness to DAA-I. According to these findings, DAA-I increases the systemic blood pressure and vascular tone in conductance and resistance vessels via AT1 receptor activation. This vasoconstrictor effect of DAA-I participates in the homeostatic control of arterial pressure, which can also contribute to the pathogenesis of hypertension. DAA-I may therefore be a potential therapeutic target in cardiovascular disease.