Comparison of the effects of acute and chronic ibotenic and quisqualic acid nucleus basalis lesioning.
The present study examines the effects of acute (1 month recovery) and chronic (8 month recovery) bilateral quisqualic (quis) and ibotenic (ibo) acid nucleus basalis (NB) lesioning on the activity of cholinergic neurons and on passive avoidance (PA) and water-maze (WM) performance. Our data demonstrate that A: The activity of choline acetyltransferase (ChAT) in cortical tissue and the number of ChAT positive neurons in the NB were decreased 1 and 8 months after quis or ibo NB lesioning. B: Ibo NB lesioning produced a greater nonspecific subcortical cell loss than quis NB lesioning. C: PA retention was impaired by acute and chronic quis and ibo NB lesioning. D: Acute ibo NB lesioning impaired acquisition and reversal learning in WM performance whereas chronic ibo NB lesioning impaired only reversal WM learning. Acute and chronic quis NB lesioning impaired reversal WM learning. The present results suggest that NB cholinergic neurons do not recover spontaneously from excitotoxin-induced damage and that they may be importantly involved in inhibitory avoidance and spatial reversal learning performance.
Riekkinen
P
P
Department of Neurology, University of Kuopio, Finland.
Riekkinen
M
M
Sirviö
J
J
Miettinen
R
R
Riekkinen
P
P
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D007051:Ibotenic Acid / Q000494:pharmacology*; D008297:Male; D009043:Motor Activity; D016318:Quisqualic Acid / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011930:Reaction Time; D013377:Substantia Innominata / Q000187:drug effects* / Q000473:pathology; D013997:Time Factors
D007051:Ibotenic Acid; D016318:Quisqualic Acid