Acute and subchronic corticosterone treatment differentially modulates subcortical limbic and neostriatal nicotinic cholinergic receptors.
The effects of acute and subchronic corticosterone treatment were analyzed on the competition by (-)nicotine ((-)nicotine hydrogen(+)-tartrate) on N-[3H]methylcarbamyl choline iodide ([ 3H]MCC) binding sites in membranes from the subcortical limbic forebrain and the neostriatum. Acute treatment with corticosterone (5 mg/kg, i.p., 2 h) increased the IC50 values of (-)nicotine by 230% in the subcortical limbic areas but not in the neostriatum. Subchronic corticosterone treatment (5 mg/kg, twice a day, 7 days) increased the IC50 values of (-)nicotine by 50% and slightly decreased the specific binding of [3H]MCC (5 nM) in the subcortical limbic area. In the neostriatum, subchronic treatment with corticosterone instead decreased by 50% the IC50 values of (-)nicotine and slightly increased the specific binding of [3H]MCC. The results indicate that corticosterone treatment selectively reduces the affinity of nicotinic cholinergic receptors within the subcortical limbic forebrain.
von Euler
G
G
Department of Histology and Neurobiology, Karolinska Institutet, Stockholm, Sweden.
Fuxe
K
K
Finnman
U B
UB
Agnati
L F
LF
D000818:Animals; D001667:Binding, Competitive / Q000187:drug effects; D002421:Caudate Nucleus / Q000187:drug effects* / Q000378:metabolism; D003345:Corticosterone / Q000494:pharmacology*; D008032:Limbic System / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D011699:Putamen / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011978:Receptors, Nicotinic / Q000187:drug effects*; D013997:Time Factors
D011978:Receptors, Nicotinic; D003345:Corticosterone