Browsing by Subject "Smooth muscle cells"
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- PublicationOpen AccessA new morpho-functional classification of the Fallopian tube based on its three-dimensional myoarchitecture(F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2001) Muglia, U.; Motta, P. M.The recent direct observations, under scanning electron microscopy (SEM), of the threedimensional architecture of myosalpinx in different mammals allows us classify salpinxes according to the myoarchitecture of their tubo-uterine junction (TUJ) and isthmus segments. Based upon the myoarchitecture of the outer wall of the TUJ we could find barrier-like species (rat and sow), sphincter-like species type a (rabbit and ewe) and sphincter-like species type b (cow and woman). The different architecture of TUJ can be explained by the different nature of the mating process. Based upon the myoarchitecture of the isthmus we could distinguish type 1 (rat) and type 2 (rabbit, ewe, sow, cow and woman) salpinxes. In the latter the close fusion of musculature deriving from the meso (extrinsic musculature) with the musculature of salpinx (intrinsic musculature) suggests the existence of a unique mesosalpinx contractile system. The myosalpinx is mostly made up of a single network of muscular fibers. Such a plexiform structure, owing to the uneven distribution of fibers, rather than producing a series of regular contraction waves, is more likely to generate random contraction waves. The random propagation of muscular network contraction may deform the plexiform wall of the myosalpinx causing the stirring of tubal contents. By such a stirring movement the contact between hormones and nutrients and the eggs or embryos is intensified, thus favoring a correct fertilization and early embryo development. Taken all together, these systematic results probably suggest an additional and rather new function for the musculature of the tube, namely to increase fertility in a large number of species.
- PublicationOpen AccessArterial wall neovascularization induced by glycerol(F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2001) Díaz Flores, L.; Gutierrez, R.; Valladares, F.; Díaz, M.; Valera, H.; Díaz Flores Jr, L.; Madrid Cuevas, Juan FranciscoAn int e nse a nd sig ni fica nt neo - vascul ari za tion, with numerous capillaries growing into th e med ia laye r o f th e rat femo ra l art e ry, was demonstrated when glycero l was administered into the interstitium be tween the femoral ve in and the femoral a rt e ry. Th e max imum mi c rovasc ul a ri za ti o n was obse rved at days 7 and 9 after glyce rol administration. Afterwards, invo lution of th e majo rit y of the new lyfo rmed microvessels in the art erial wall occurred. Other substances containing glyce rol in their molecul es, such as tri ace tyl-glyce rol and tri butyril-glyce rol, fa il ed to produce significant neovascul ari zation in the medi a laye r of the femora l art ery. Neova cul ariza tion of the art eri al wa ll was preceded by a co nside rab le dec rease in the number of the smooth muscle ce lls, whi ch ex perienced apoptosis and necrobiosis, disappearing in extense areas of the arteri al segment affected by glyce rol. Coinciding with neovascul ariza tion and mi crovascul ar in volu tion, repopul ation of the med ia laye r by smooth mu 'cle cells was observed.
- PublicationOpen AccessFlavonoids inhibit the platelet TxA2 signalling pathway and antagonize TxA2 receptors (TP) in platelets and smooth muscle cells(Wiley, British Pharmacological Society, 2007-04-10) Guerrero López, José Antonio; Navarro-Nuñez, Leyre; Lozano Almela, María Luisa; Martínez, Constantino; Vicente García, Vicente; Gibbins, Jonathan M.; Rivera Pozo, José; Medicina Interna; Medicina; Facultad de MedicinaAims: Flavonoids may affect platelet function by several mechanisms, including antagonism of TxA2 receptors (TP). These TP are present in many tissues and modulate different signalling cascades. We explored whether flavonoids affect platelet TP signalling, and if they bind to TP expressed in other cell types. Methods: Platelets were treated with flavonoids, or other selected inhibitors, and then stimulated with U46619. Similar assays were performed in aspirinized platelets activated with thrombin. Effects on calcium release were analysed by fluorometry and changes in whole protein tyrosine phosphorylation and activation of ERK 1/2 by Western blot analysis. The binding of flavonoids to TP in platelets, human myometrium and TPaand TPb-transfected HEK 293T cells was explored using binding assays and the TP antagonist 3H-SQ29548. Results: Apigenin, genistein, luteolin and quercetin impaired U46619-induced calcium mobilization in a concentration-dependent manner (IC50 10–30 mm). These flavonoids caused a significant impairment of U46619-induced platelet tyrosine phosphorylation and of ERK 1/2 activation. By contrast, in aspirin-treated platelets all these flavonoids, except quercetin, displayed minor effects on thrombin-induced calcium mobilization, ERK 1/2 and total tyrosine phosphorylation. Finally, apigenin, genistein and luteolin inhibited by >50% 3H-SQ29548 binding to different cell types. Conclusions: These data further suggest that flavonoids may inhibit platelet function by binding to TP and by subsequent abrogation of downstream signalling. Binding of these compounds to TP occurs in human myometrium and in TP-transfected HEK 293T cells and suggests that antagonism of TP might mediate the effects of flavonoids in different tissues.
- PublicationOpen AccessNeurotrophins, airway smooth muscle and the fetal breathing-like movements(Murcia : F. Hernández, 2006) Inanlou, M.R.; Baguma-Nibasheka, M.; Keating, M.M.; Kablar, B.Central nervous system and skeletal muscles secrete a group of polypeptide hormones called neurotrophins (NTs). More recent studies show that NTs and their receptors are also expressed in the lung, suggesting a role for NTs in lung development. To examine the role of NTs during normal and diseased lung organogenesis, we employed wild-type and amyogenic mouse embryos (designated as Myf5-/- :MyoD-/-). Amyogenic embryos completely lacked skeletal muscles and were not viable after birth due to the respiratory failure secondary to lung hypoplasia. To examine the importance of lung-secreted NTs during normal and hypoplastic lung organogenesis, immunohistochemistry was employed. Distribution of NTs and their receptors was indistinguishable between normal and hypoplastic lungs. To further examine the importance of non-lung-secreted NTs (e.g., from the skeletal muscle and CNS) in lung organogenesis, in utero injections of two NTs were performed. The exogenously introduced NTs (i.e., non-lung-secreted) did not appear to improve development of the lung in amyogenic embryos. Moreover, immunohistochemistry showed significantly reduced number of airway smooth muscle cells (ASMCs) in hypoplastic lungs of amyogenic embryos, suggesting that the number of ASMCs is primarily regulated by the fetal breathing-like movements (i.e., mechanical factors).
- PublicationOpen AccessPolyglucosan bodies in the prostatic stromal smooth muscles of aged dogs(Universidad de Murcia. Departamento de Biología Celular e Histología, 2017) Kamiya, Shinji; Yoshimura, Hisashi; Okada, Keina; Yoshida, Ayaka; Fukuda, Yuki; Yamamoto, Masami; Soeta, Satoshi; Takahashi, KimimasaPolyglucosan bodies (PGB) in the prostate of aged dogs without neurological signs were examined by light microscopy, histochemistry and immunohistochemistry. Prostatic PGB were round or oval and slightly basophilic. Most of the bodies were situated within the stromal smooth muscle cells. PGB were intensely positive for PAS, Best’s carmine, Lugol’s iodine and Grocott’s methenamine silver method. Moreover, canine prostatic PGB were immunoreactive for monoclonal antibodies raised against human polyglucosan. The frequency of PGB in the smooth muscle cells was significantly correlated with the age of dogs. The occurrence of PGB in the canine prostate might be a non-specific finding related to ageing.
- PublicationOpen AccessStem cells, vascular smooth muscle cells and atherosclerosis(Murcia : F. Hernández, 2006) Margariti, A.; Zeng, L.; Xu, Q.Stem cells have the ability to differentiate into a variety of cells to replace dead cells or to repair tissue. Recently, accumulating evidence indicates that mechanical forces, cytokines and other factors can influence stem cell differentiation into vascular smooth muscle cells (SMCs). In developmental process, SMCs originate from several sources, which show a great heterogenicity in different vessel walls. In adult vessels, SMCs display a less proliferative nature, but are altered in response to risk factors for atherosclerosis. Traditional view on SMC origins in atherosclerotic lesions is challenged by the recent findings that stem cells and smooth muscle progenitors contribute to the development of atherosclerotic lesions. Vascular progenitor cells circulating in human blood and the presence of adventitia in animals are recent discoveries, but the source of these cells is still unknown. The present review gives an update on the progress of stem cell and SMC research in atherosclerosis, and discusses possible mechanisms of stem/progenitor cell differentiation that contribute to the disease process.
- PublicationOpen AccessThe three-dimensional architecture of the myosalpinx in the rat (Rattus norvegicus) as revealed by scanning electron microscopy(Murcia : F. Hernández, 1996) Muglia, U.; Vizza, E.; Correr, S.; Germaná, G.; Motta, P.M.The three-dimensional (3-D) architecture of myosalpinx in the rat has been investigated by means of scanning electron microscopy after microdissection and removing interstitial connective tissue with 6N NaOH digestion. In the extramural portion of tube-uterine junction the myosalpinx shows circularly arranged fibers originating from the uterus, together with oblique fibers typical for the salpinx, which occur more frequently in the deeper layers. As fibers approach the mucous folds they assume a plexiform arrangement, which is maintained through all tubal segments. In the isthmus surface fibers form wide muscle rings around the elbow of loops, peculiar to the rat tubal morphology. Surface fibers in the ampulla and pre-ampulla have an even circular course. Our 3-D results reveal that the muscular architecture of rat tube is mainly organized in concentric, monolayered shells with a plexiform arrangement tightly fastened together. Functionally, this muscular arrangement seems to be capable of stirring rather than pushing the embryo and gametes. Finally, such a plexiform network might work as a mechanism of (
- PublicationOpen AccessTopographical difference of cytoskeletal organization in smooth muscle cells of rat duodenum revealed by quick-freezing and deep-etching method(Murcia : F. Hernández, 2000) Takayama, I.; Fuji, Y.; Terada, N.; Baba, T.; Kato, Y.; Fujino, M.A.; Ohno, S.The sarcolemmal domain of rat duodenal smooth muscle cells includes caveolae and associated cytoskeletal or filamentous elements. We have used the quick-freezing, deep-etching method to examine the three dimensional relationships between these components. Replica membranes for separated strips of rat duodenal muscle layers were routinely prepared after extraction soluble proteins from cytoplasm and extracellular matrix. As results, 1) cytoskeletal elements in smooth muscle cells consisted mainly of striated thin filaments; 2) thin filaments were connected with some plasma membranes through filaments associated with the sarcolemma, which formed fine network structures beneath the sarcolemma; 3) many bridging structures between the filaments associated with the sarcolemma and the extracellular matrix were frequently detected in the plasma membrane; and 4) compact filaments associated with the sarcolemma almost disappeared near the caveolae, and only thin filaments were anchored to their neck parts. The special arrangement of the cytoskeletal components, which is probably necessary for the intestinal motility, characterizes the topographical difference of the smooth muscle sarcolemma.