[The effect of proxodolol on systemic and regional hemodynamics].

The effect of the new hybrid (beta-, alpha-) adrenoceptor blocking drug proxodolol on cardiac output and its distribution between 16 vascular regions, by using the microsphere method on anesthesized normotensive rats and rats with persistent renovascular hypertension. Proxodolol given in beta-adreno-blocking doses similar to those of labetalol was shown to exert vasodilating effects in normotensive rats. Renal, adrenal, splenic, and skeletal muscle vessels were most sensitive to labetalol, whereas cardiac and pulmonary vessels were responsive to proxodolol.

[Proxodolol--a new beta- and alpha-adrenoblockader].

The beta- and alpha-adrenoceptor blocking activity, the specificity of its beta-adrenoceptor blocking action, partial agonistic and membrane-stabilizing properties, as well as antihypertensive, antiarrhythmic, and anti-ischemic effects were studied. Proxodolol was shown to be superior to labetalol in its beta-adrenoceptor blocking action and similar to it in its alpha-adrenoceptor blocking agent. The drug has no a partial agonistic activity and produces a moderate membrane-stabilizing action.

[Wall thickness of skeletal muscle microvessels and their reactivity to vasoconstrictor stimuli in normal rats and rats with spontaneous hypertension].

Wall thickness (w), wall thickness to lumen radius ratio (w/r) and vasomotor reactions produced by electrical stimulation of the sympathetic tract were studied by intravital microscopy of the skeletal muscle (extensor hallucis proprius) and compared in normal Wistar rats (NWR) and spontaneously hypertensive rats (SHR). It was established that w and w/r of arterioles with an equal lumen was greater in SHR than in NWR. Sympathetic stimulation with 6 mA, 3 imp/sec for 10 sec produced an almost 50% reduced arteriolar constriction in SHR, as compared to NWR.