Ec. Clayton et Cl. Williams, Glutamatergic influences on the nucleus paragigantocellularis: Contribution to performance in avoidance and spatial memory tasks, BEHAV NEURO, 114(4), 2000, pp. 707-712
Stimulation of the locus coeruleus (LC) and the subsequent release of norep
inephrine contribute to memory consolidation processes. Excitatory input to
the LC is derived primarily from neurons in the nucleus paragigantocellula
ris (PGI). The authors examined the effects of activating the pathway betwe
en PGi and the LC on memory. Rats received Vehicle or the excitatory amino
acid glutamate (25, 50, or 100 nmol/0.5 mu l) into PGi after training in an
inhibitory avoidance (IA) or delayed matching-to-sample (DMS) task. Rats g
iven the 100-nmol dose had significantly longer retention latencies on a 48
-hr LA retention test. Rats treated with the 50- or 100-nmol dose made sign
ificantly more correct responses than controls on an 18-hr DMS retention te
st. Results suggest that encoding and storage of memory for emotional and s
patial events may be enhanced by activation of neuronal circuits afferent t
o the LC.