Pharmacological regulation of descending cortical control of the nociceptive processing.

Clinical and experimental data indicate that the cerebral cortex plays an important role in pain perception and endogenous antinociceptive system function. Moreover, the enhancement of descending inhibitory cortical control may be involved in the mechanisms of analgetic effect of some agents. The present study was designed to investigate the effect of cortical electrical stimulation (as a model of descending inhibitory control) on the behavioral and electrophysiological signs of nociceptive response, decipher the mechanisms involved therein and evaluate the action of central analgesics (both opioid and non-opioid) on descending cortical control.

[Inhibition of thalamic activity by stimulation of the inferior raphe nucleus in the chronically awake cat].

Poly U dependent polyphenylalanine synthesis from 14C phenylalanyl-tRNA, under known optimal conditions, in ribosomes obtained from NaF-treated Rabbit reticulocytes, is only slightly stimulated by the addition of ATP, GTP and UTP in the absence of phosphoenolpyruvate and pyruvate kinase. However, in the presence of the energy generating system, the stimulation by ATP far surpasses that by other nucleotides. A scheme of reactions which help explain this observation is presented.