Immature rat convulsions and long-term effects on hippocampal cholinergic neurotransmission.
Generalized tonic-clonic convulsions were induced on 2 consecutive days by pentylenetetrazol (PTZ) in immature rats (postnatal days 10 and 20), and hippocampal slices were prepared at different intervals post-injection. The anticholinesterase eserine provoked interictal-like discharges in the CA3 area of PTZ-injected rats (19/33), but not in controls (0/15), an effect mimicked by carbachol and reversed by atropine. This enhanced response to eserine was recorded in slices from 25-100% of the PTZ-injected rats, the percentage varying with the age at injection and post-injection interval. These results suggest that seizures in immature brain may have long-term consequences in cholinergic neurotransmission, converting a rise in endogenous ACh into an epileptogenic stimulus, which in turn would presumably facilitate the recurrence of seizures.
Meilleur
S
S
Ste-Justine Hospital Research Center and Dept of Pediatrics, Faculty of Medicine, Université de Montréal, QC, Canada.
Carmant
L
L
Psarropoulou
C
C
D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D002799:Cholinergic Fibers / Q000187:drug effects / Q000502:physiology*; D002800:Cholinesterase Inhibitors / Q000494:pharmacology; D003292:Convulsants; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects; D006624:Hippocampus / Q000187:drug effects / Q000503:physiopathology*; D066298:In Vitro Techniques; D010433:Pentylenetetrazole; D010830:Physostigmine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012640:Seizures / Q000139:chemically induced / Q000503:physiopathology*; D009435:Synaptic Transmission / Q000187:drug effects; D013997:Time Factors
D002800:Cholinesterase Inhibitors; D003292:Convulsants; D010830:Physostigmine; D000109:Acetylcholine; D010433:Pentylenetetrazole