Tonic function of nicotinic receptors in stress-induced release of L-DOPA from the nucleus accumbens in freely moving rats.
We investigated whether stress induces the release of L-3,4-dihydroxyphenylalanine (DOPA) and dopamine from the nucleus accumbens in conscious rats and characterized the stress-induced response. Electrical foot-shock stress induced both DOPA and dopamine release, measured by microdialysis, from the nucleus accumbens in freely moving rats. Pretreatment of rats with mecamylamine completely blocked stress-induced DOPA release, but only partially blocked dopamine release. Diazepam did not affect the foot-shock-induced release of DOPA, while the same dose of diazepam partially blocked the stress-induced release of dopamine. These findings suggest a tonic function of central nicotinic receptors in stress-induced DOPA release from the nucleus accumbens in conscious rats.
Yamanashi
K
K
Department of Pharmacology, Yokohama City University School of Medicine, Yokohama 236-0004, Japan.
Miyamae
T
T
Misu
Y
Y
Goshima
Y
Y
D000818:Animals; D000927:Anticonvulsants / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects; D003975:Diazepam / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism; D004597:Electroshock; D005528:Foot; D007980:Levodopa / Q000378:metabolism*; D008297:Male; D008464:Mecamylamine / Q000494:pharmacology; D017551:Microdialysis; D009043:Motor Activity / Q000187:drug effects; D009068:Movement; D018733:Nicotinic Antagonists / Q000494:pharmacology; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011978:Receptors, Nicotinic / Q000187:drug effects / Q000502:physiology*; D013312:Stress, Physiological / Q000503:physiopathology*
D000927:Anticonvulsants; D018733:Nicotinic Antagonists; D011978:Receptors, Nicotinic; D007980:Levodopa; D008464:Mecamylamine; D003975:Diazepam; D004298:Dopamine