Chronic and single administration of pentylenetetrazol modifies benzodiazepine receptor-binding: an autoradiographic study.
Benzodiazepine (BDZ) receptor-binding changes in the rat brain induced by pentylenetetrazol (PTZ) were investigated by in vitro autoradiography. Our experiments revealed that a single PTZ administration produced BDZ-binding decrease in cingulate, frontal, temporal, parietal and piriform cortices; caudate putamen; medial, basolateral and cortical amygdaloid nuclei; medial, ventromedial and ventroposterior thalamic nuclei; substantia nigra pars compacta and periaqueductal gray. Fully kindled rats with chronic PTZ treatment showed reduced BDZ receptor-binding in cingulate, frontal, parietal and piriform cortices; caudate putamen; medial, ventromedial and ventroposterior thalamic nuclei; and periaqueductal gray. These effects resulted from decrease in the binding capacity. Our results support that PTZ-induced chemical kindling may be associated with significant changes of the GABAergic systems and BDZ-binding from the first administration.
Rocha
L
L
Instituto Mexicano de Psiquiatría, División de Neurociencias, México, DF, Mexico.
Ackermann
R F
RF
Engel
J
J
D000818:Animals; D014151:Anti-Anxiety Agents / Q000493:pharmacokinetics; D001345:Autoradiography; D003292:Convulsants / Q000008:administration & dosage / Q000494:pharmacology*; D003720:Densitometry; D005445:Flunitrazepam / Q000493:pharmacokinetics; D008297:Male; D010433:Pentylenetetrazole / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011963:Receptors, GABA-A / Q000187:drug effects*; D012640:Seizures / Q000139:chemically induced
D014151:Anti-Anxiety Agents; D003292:Convulsants; D011963:Receptors, GABA-A; D005445:Flunitrazepam; D010433:Pentylenetetrazole