RESUMO
The authors admit that the conjunctive-muscular constitution of the walls of the superior venae cavae throughout the length of the intrapericardium segment and the debouchement in the right atrium, associated with the presence of a myocardium sheath can be made up of a functional device of sphincter form able to act on the control of the blood flow to the interior of the arterial chamber as well as stopping blood flow during the arterial systole. The fixation of the venous wall to the deep chamber of the serous pericardium, contributes to growth in resistance during the elevation of venous pressure, making possible the preservation of integrity of the superior venae cavae. The expansion of fasciculi of nodal fibers in the right wall of the superior venae cavae permits that the unlocked impulse in the S-A node also reaches the vascular wall contributing to the shortening and diminuation in caliber of the vein.
Assuntos
Envelhecimento/fisiologia , Coração/anatomia & histologia , Pericárdio/anatomia & histologia , Veia Cava Superior/anatomia & histologia , Adulto , Feminino , Átrios do Coração/anatomia & histologia , Humanos , Masculino , Pessoa de Meia-Idade , Veia Cava Superior/ultraestruturaRESUMO
The coronary sinus was investigated in 34 normal adult dogs, in order to verify its formation, tributaries, length and the valves, as well as the relationship of the venous walls to the epicardium and to the myocardium. The valve of the coronary sinus was observed in only 4 cases (1.7%). In 30 cases (98.3%) the ostium of the coronary sinus was lacking a valve. The valve of Vieussens double, was found at the level of the transition between the great cardiac vein and the coronary sinus, as well as others parietal venous valves. A comparison with the human pattern was made, particularly regarding the action of the valve of the coronary sinus and the formation of the sinus.
Assuntos
Vasos Coronários/anatomia & histologia , Cães/anatomia & histologia , Animais , Feminino , MasculinoRESUMO
Os autores observaram a origem da artéria carótida interna diretamente da aorta, entre o tronco braquiocefálico e a artéria subclávia esquerda. Tal ocorrência se deu em uma cobaia fêmea com 260 g de peso. Esta variação ocorreu uma única vez entre 50 animais dissecados e estudados para outros fins, porém ligados à pesquisa do sistema arterial cervical
Assuntos
Animais , Cobaias , Artérias Carótidas/anatomia & histologiaAssuntos
Masculino , Feminino , Animais , Cricetinae , Circulação Coronária , Vasos Coronários , Ventrículos do CoraçãoRESUMO
A vascularizacao arterial da pelve em gato, coelho e roedores de laboratorio no que concerne as origem, ramescencia e distribuicao dos vasos pelvicos (inclusive dos ramos terminais da aorta), foi estudada. Nestes estudos foi descrito, com especial enfase, o comportamento arterial dos ramos viscerais das arterias iliacas internas (aa. umbilical e urogenital), concernente a vascularizacao dos orgaos pelvicos nestas especies. Estas informacoes sao agregadas e relatadas no presente trabalho e todos os dados sao comparativamente discutidos com outras informacoes da literatura especializada
