[Effect of hypothalamic stimulation on the appearance of the early and delayed responses of the somato-sympathetic reflex].

Stimulation of somatic nerves evoked in the cat L2--L3 white rami a late two--wave response. High frequency stimulation of the hypothalamus induced an increase of the blood pressure, facilitation of the first component and suppression of the second component of the late response. The components of the early response were insignificantly affected by the stimulation. The paired stimuli technique revealed interaction of descending and peripheral afferent excitation of sympathetic preganglionic neurons. The role of baroreceptor and hypothalamic excitation in spinal sympathetic mechanisms is discussed.