RESUMO
Smooth muscle cells from the arterial wall of placental chorion were studied at 39-40-week gestation. The content of mono- and binuclear tetraploid myocytes was higher in sites of arterial branching and turns (27.3% vs. 4.4% straight parts of the arteries; DNA cytophotometry data). Mitoses were found only in these arterial regions (0.18%). Regional changes in the sizes of diploid and polyploid myocytes were detected, associated with the blood flow pattern in the chorion; myocyte hypertrophy was 17-fold more incident in sites of arterial turns and branching than in straight arteries. Possible causes of changes in the proliferative characteristics and subsequent growth of the chorionic arterial wall myocytes are discussed.
Assuntos
Artérias/citologia , Núcleo Celular/ultraestrutura , Córion/irrigação sanguínea , Miócitos de Músculo Liso/citologia , Placenta/irrigação sanguínea , Ploidias , Velocidade do Fluxo Sanguíneo , Separação Celular/métodos , Forma Celular , Córion/citologia , DNA/química , Feminino , Humanos , Índice Mitótico , Fenótipo , Placenta/citologia , Gravidez , Cultura Primária de CélulasRESUMO
Structure of the placental arterial bed was studied using histological and morphometric methods. The formation of smooth muscle regulatory complexes in blood vessels of the chorionic plate and chorionic villi was demonstrated. These complexes are genetically determined and represent a variant of compensatory and adaptive reorganization of the placental arteries for adequate fetoplacental blood supply under normal conditions and placental underdevelopment.
Assuntos
Artérias/anatomia & histologia , Músculo Liso Vascular/fisiologia , Placenta/irrigação sanguínea , Adulto , Pesos e Medidas Corporais , Citofotometria , Feminino , Glicogênio/metabolismo , Técnicas Histológicas , Humanos , Placenta/anormalidades , GravidezRESUMO
Study of smooth myocytes in coronary arteries of dogs with experimental coarctation of the aorta revealed increased DNA content in myocyte nuclei and increased percentage of binucleated cells. Polyploidy of vascular myocytes did not disappear after correction of the aortal defect.
Assuntos
Coartação Aórtica/patologia , Vasos Coronários/patologia , Células Musculares/citologia , Células Musculares/patologia , Animais , Coartação Aórtica/diagnóstico por imagem , Modelos Animais de Doenças , Cães , Hipertensão/patologia , RadiografiaRESUMO
Brain and kidneys from 15 control and 70 experimental puppies with hemodynamic model of coarctation of the aorta were examined. The number of regulatory muscle formations was increased in the brain and decreased in the kidneys during modeling of aorta coarctation associated with hyper- and hypotension in the corresponding basins. The location of these structures in cerebral and renal distribution and resistance vessels is analyzed.
