[Topography and hydrodynamic heterogeneity in the terminal bed of the vessels of the gastrocnemius muscle of the cat].

The cine-TV technique acided to reconstruct the in vivo pattern of the vascular bed surface in the m. gastrocnemius of anesthetized cats. Existence of microvascular elements (modules) was confirmed as regularly repeated every 400-500 mus along the muscular fibers. A module includes transversal (oblique) precapillary arteriole and postcapillary venule interconnected with 3-12 parallel capillaries. Mean blood velocity in the capillaries was initially 0.73 +/- 0.12 mm/sec and during postelongation hyperemia it was 0.91 +/- 0.13 mm/sec, the velocity being slower in distal capillaries. This diversity was reduced in postelongation hyperemia. Mathematical modelling of blood flow distribution over different types of modules showed the blood flow velocity in the capillaries to depend on the ratio: total resistance of incoming and outgoing vessels against the resistance of the capillary part. Along with diminishing of the ratio, the diversity of perfusion must also diminish which has been corroborated in the course of experiments.