Parabrachial gustatory lesions impair taste aversion learning in rats.
Lesions in the gustatory zone of the parabrachial nuclei (PBN) severely impair acquisition of a conditioned taste aversion (CTA) in rats. To test whether this deficit has a memorial basis, intact rats (n = 15) and rats with PBN lesions (PBNX; n = 10) received seven intraoral taste stimulus infusions (30 s, 0.5 ml) distributed over a 30.5-min period after either LiCl or NaCl injection. This task measures the rapid formation of a CTA and has minimum demands on memory. LiCl-injected intact rats progressively changed their oromotor response profile from one of ingestion to one of aversion. NaCl-injected intact rats did not change their ingestive pattern of responding. In contrast, there was no difference between LiCl- and NaCl-injected PBNX rats. These same PBNX rats failed to avoid licking the taste stimulus when tested in a different paradigm. A simple impairment in a memorial process is not likely the basis for the CTA deficit.
Spector
A C
AC
Department of Psychology, University of Pennsylvania.
Norgren
R
R
Grill
H J
HJ
D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D001362:Avoidance Learning / Q000502:physiology*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology; D002712:Chlorides / Q000633:toxicity; D003214:Conditioning, Classical / Q000502:physiology*; D004292:Dominance, Cerebral / Q000502:physiology; D008094:Lithium / Q000633:toxicity; D018021:Lithium Chloride; D008297:Male; D008526:Medulla Oblongata / Q000502:physiology*; D011149:Pons / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D013569:Synapses / Q000502:physiology; D013649:Taste / Q000502:physiology*; D013650:Taste Buds / Q000502:physiology*
D002712:Chlorides; D008094:Lithium; D018021:Lithium Chloride