[Effect of angiotensin II and naloxone on the nociceptive sensitivity of rabbits undergoing electrostimulation of the skin and dental pulp].

In unanesthetized rabbits intraventricular and intravenous administration of angiotensin II resulted in a decrease of the somatosensory evoked potential amplitude in response to nociceptive electrodental stimulation but not nociceptive electrocutaneous stimulation. Saralasin administered intraventricularly abolished the effect of angiotensin II. Naloxone injected by the same route increased the evoked potential amplitude in response to electrodental but not to electrocutaneous stimulation and also reversed the analgesic effect of angiotensin II. The selectivity of the antinociceptive effect of angiotensin II is probably due to the presence of different specific peptide pain mechanisms of varying origin.