[Neurogenic changes in filtration-absorptive ratios in skeletal muscle vessels]

In cats, the volumometry of extracorporeally circulating blood revealed that the character of changes of the capillary hydrostatic pressure in the hindlimb skeletal muscles occurring in response to stimulation of the lumbar sympathetic string, virtually depends on the mode of perfusion: under constant blood flow the capillary pressure increased while in perfusion under constant pressure it decreased. The capillary filtration coefficient (CFC) increased in response to stimulation of sympathetic efferents irrespective of the mode of vascular bed perfusion. The mechanisms of the above changes of the capillary hydrostatic pressure are considered from the standpoint of participation of hemodynamic factors and active shifts of pre-and postcapillary pressure. Possible role of the change of the vascular bed permeability and activation of beta-adrenoreceptors in the mechanism of the capillary filtration coefficient increase, is discussed.