Inhibition of the tail flick reflex following microinjection of morphine into the amygdala. Neuroreport 1993 May;4(5):471-4
Date
05/01/1993Pubmed ID
8513121DOI
10.1097/00001756-199305000-00002Scopus ID
2-s2.0-0027294726 (requires institutional sign-in at Scopus site) 65 CitationsAbstract
Recent evidence indicates that the amygdala plays a critical role in the activation of brain stem antinociceptive systems during stress. In the present experiment, bilateral microinjection of morphine sulfate (10 micrograms) into the amygdala of pentobarbital-anesthetized rats resulted in a time-dependent elevation in latency of the tail flick reflex evoked by radiant heat. The most effective sites within the amygdala were in or immediately adjacent to the basolateral nucleus. The relative amplitude of the tail flick reflex did not differ as a function of repeated testing or morphine treatment. These results suggest that important forebrain inputs which normally activate endogenous antinociceptive systems in behaving animals may be manipulated and studied in detail using the anesthetized rat.
Author List
Helmstetter FJ, Bellgowan PS, Tershner SAAuthor
Fred Helmstetter PhD Professor in the Psychology / Neuroscience department at University of Wisconsin - MilwaukeeMESH terms used to index this publication - Major topics in bold
AmygdalaAnimals
Male
Microinjections
Morphine
Nociceptors
Pain Measurement
Rats
Rats, Sprague-Dawley
Reflex
Regional Blood Flow
Skin Temperature
Spinal Cord
