Abstract: | Principles governing changes in diameter of the lumen and area of the endothelium of capillaries in the parotid salivary gland of rats with an experimentally established 3-h secretory cycle, and also during circulatory ischemia of the organ for 5 min, were studied. The diameter of the lumen and area of the endothelium of the capillaries changed very little with the phase of the secretory cycle. Occlusion of the common carotid artery for 5 min likewise did not change the diameter of the lumen or the area of the endothelium of the capillaries. The results suggest that the increase in the transcapillary blood flow during secretion can be explained by the recruiting of more capillaries into the circulation.Laboratory of Electron Microscopy, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Kupriyanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 80, No. 7, pp. 104–106, July, 1975. |