[The effect of transcranial electrostimulation in an analgesic regimen on somatosympathetic reflexes].

The mechanisms of inhibitory effect of transcranial electrostimulation in analgesic regime on blood pressor nociceptive reflexes were studied in experiments in rabbits and cats. Considerable inhibition of the late (bulbar) somato-sympathetic reflexes and spino-bulbo-spinal somato-somatic reflexes as well was demonstrated. The probable basis of sympatho-inhibition during transcranial electrical stimulation is a reduction of excitatory input to bulbar sympathoexcitatory neurons.

[Role of sympatho-activating structures of the ventrolateral surface of the medulla oblongata in vasomotor regulation].

In anesthetized cats, the cold block or coagulation of intermediate zones of the bulbar ventro-lateral surface (BVLS) resulted in profound decrease of the blood pressure (BP) level. The descending tonic activation of spinal vasomotor mechanism in formed by spontaneous discharges of antidromically identified output sympatho-activating neurons with mean firing rate about 14.4/sec.

[Neuronal organization of the sympathetic system-activating structures of the ventro-lateral surface of the medulla oblongata].

In anesthetized cats, activating effects of the bulbar ventro-lateral surface (BVLS) upon the spinal sympathetic neurons were shown to be transmitted via output sympathoactivating neurons (OSN) with descending axons. Antidromic discharge of these neurons elicited by stimulation of the spinal dorso-lateral funiculus were found in the intermediate zone of the BVLS at the depth of about 400-2000 mu. Stimuli applied to different regions of the BVLS activate at least two groups of surface fibers (conducting velocities 6.

[Nonuniformity of the descending pathways activating the sympathetic preganglionic neurons of the superior thoracic segment of the spinal cord].

In anesthetized, immobilized and artificially ventilated cats, excitatory influences from the ventrolateral part of medulla are mediated to sympathetic preganglionic neurons of T2 segment via two types of descending pathways with conduction velocity 12.3 +/- 3.2 m/sec and about 6 m/sec.