مطالعه مقايسه اي بافت شناسي گره سينوسي دهليزي قلب درد و سن مختلف جنين گوسفند

Comparative histological study of the cardiac sinu-atrial node in two different ages of ovine fetus

The sinu-atrial node (SAN) enables the heart to pulsate continuously by producing impulses. Regarding that cardiovascular disorders are among the main causes of death in human being and as the histological information about the SAN of ovine fetuses is basically needed in various fields of animal sciences, such as histology, anatomy, physiology, pathology and cardiology, the present study was planned to provide this basic information in this area. A detailed study was conducted on the SAN of two and four month fetuses (n= 4 each). Its shape was relatively cone shaped. The cells of the ovine fetus were occurred as strands of cells. There were color differences between those and the ordinary myocardial cells of the right atrium. This difference and also the amount of collagen frame and nerve supply were greater in four month old fetuses. In general, the percentage of P cells in the SAN of ovine fetus was high and the number of these cells was higher in two month fetuses compared with four months old. There were one or some arterioles near the periphery of the cranial and at the interatrial septum, which supply it. The results were compared with the available data on the human being and other species and the clinical significance of some of the results have been discussed