Acute reduction of brain substance P induced by nicotine.
Ten minutes after a single injection of 0.8 mg/kg nicotine SC (free base) the level of substance P-like immunoreactivity (SPLI) was reduced by 61-73% in rat caudate-putamen, nucleus accumbens, and olfactory tubercle, with smaller and not significant reductions in the frontal cortex, substantia nigra, and ventral tegmental area. The nicotinic receptor antagonist mecamylamine (1.0 mg/kg IP) prevented the reductions in SPLI. The rapidity and the degree of the changes in SPLI after nicotine exceed those previously reported for other agents and implicate substance P neurotransmission as a major component of nicotinic action.
Naftchi
N E
NE
Institute of Rehabilitation Medicine, NYU Medical Center, New York.
Maker
H
H
Lapin
E
E
Sleis
J
J
Lajtha
A
A
Leeman
S
S
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D008464:Mecamylamine / Q000494:pharmacology; D009538:Nicotine / Q000494:pharmacology*; D009928:Organ Specificity; D051381:Rats; D011919:Rats, Inbred Strains; D013373:Substance P / Q000378:metabolism*
D013373:Substance P; D008464:Mecamylamine; D009538:Nicotine