[Coefficient of capillary filtration and distensibility of small intestine vessels at various levels of blood flow and venous and perfusion pressure].
In the cat decentralized small intestine perfused with a constant blood volume, the capillary filtration coefficient (CFC) increased from 0.02 to 0.22 ml/min/mm Hg/100 g on increase of the venous pressure from 0 to 18 mm Hg. The stretching ability of the intestinal veins was maximal at mean values of the venous pressure (6-18 mm Hg) and decreased at low (0-3 mm Hg) and high (24 mm Hg) values. At 6-24 mm Hg, a vein-arteriolar response occurred consisting of two components: a fast short (20-30 sec) and a slow one (stable). Changes within the large range of blood flow (30-170%) and perfusion pressure (30-170 mm Hg) did not affect the CFC or the stretching ability. In the blood flow decreased by 25, 50 and 75%, the O2 extraction from the blood consistently increased, the O2 consumption was slightly reduced, and the CFC did not change. A hypothesis is advanced that the intestine precapillary sphincters are more sensitive to decrease of the arterial blood pO2 than to decrease of the O2 total transport to the intestine due to reduction of the blood flow.
D000818:Animals; D001794:Blood Pressure; D001808:Blood Vessels / Q000502:physiology*; D002199:Capillary Permeability; D002415:Cats; D004548:Elasticity; D005260:Female; D006439:Hemodynamics; D007421:Intestine, Small / Q000098:blood supply* / Q000378:metabolism; D008297:Male; D010101:Oxygen Consumption; D014680:Veins / Q000502:physiology; D014690:Venous Pressure
Koeffitsient kapilliarnoĭ fil'tratsii i rastiazhimost' sosudov tonkogo kishechnika pri raznykh urovniakh krovotoka, venoznogo i perfuzionnogo davleniia.