[Decrease in the effectiveness of a hypoxic stimulus during cooling of the vascular bed of an organ].

Acute experiments on cats using perfusion of the innervated calf muscle and small intestinal vessels with self blood at a constant blood flow rate have established decreased sensitivity of vessels (cooled to 30 degrees C) to hypoxic stimulus effect (inhalation of 10% O2 in N2). The essence of the phenomenon consists in considerably smaller deviations of pre- and postcapillary resistance, capillary filtration coefficient, mean capillary pressure during simultaneous exposure to cold and hypoxia than during separate application of hypoxic or hypothermic stimuli. Organ distinctions in the degree and direction of changes in vascular resistance and metabolism have been observed.