Hippocampal long-term potentiation in nucleus basalis magnocellularis-lesioned rats.
The probability of hippocampal long-term potentiation induction in the mossy fiber CA3 and commissural/associational CA3 responses and the cortical levels of choline acetyltransferase (ChAT) activity were compared in right nucleus basalis magnocellularis (NBM)-lesioned rats. A 50% reduction in the right cortical ChAT activity was demonstrated 4 weeks after an ibotenic acid lesion of the NBM. No significative differences were found in the probability of LTP induction of right hippocampal slices in sham-operated rats from 10 to 40 days after the injection into the right NBM. On the contrary, a progressive and significative increase in the probability of LTP induction was shown in right hippocampal slices of NBM-lesioned rats from 10 to 40 days after the injection of ibotenic acid into the right NBM. The results demonstrated the appearance of a paradoxical increase of hippocampal synaptic plasticity when the cortical cholinergic biochemical alterations are still present. This finding might be responsible for a behavioural recovery, in NBM-lesioned rats.
Frank
C
C
Laboratorio di Farmacologia, Istituto Superiore di Sanità, Roma, Italy.
Sagratella
S
S
Niglio
T
T
Caporali
M G
MG
Bronzetti
E
E
Scotti de Carolis
A
A
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects / Q000502:physiology; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D004558:Electric Stimulation; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D007051:Ibotenic Acid; D066298:In Vitro Techniques; D008297:Male; D016202:N-Methylaspartate / Q000037:antagonists & inhibitors; D009412:Nerve Fibers / Q000187:drug effects / Q000502:physiology; D009847:Olivary Nucleus / Q000502:physiology*; D011712:Pyramidal Tracts / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013238:Stereotaxic Techniques
D007051:Ibotenic Acid; D016202:N-Methylaspartate; D015763:2-Amino-5-phosphonovalerate; D002795:Choline O-Acetyltransferase