Nimodipine reduction of naltrexone-precipitated locus coeruleus activation and abstinence behavior in morphine-dependent rats.
Single-unit recordings in anesthetized animals revealed that the L-type calcium channel antagonist, nimodipine (10 mg/kg), attenuated the activation of locus coeruleus neurons produced by naltrexone in opiate-dependent rats. Nimodipine also dose-dependently (1 mg/kg, 10 mg/kg, IP) inhibited the display of naloxone-precipitated withdrawal behaviors with a time course similar to that of nimodipine effects on the locus coeruleus. These data suggest that nimodipine may suppress opiate withdrawal via noradrenergic mechanisms.
Krystal
J H
JH
VA-Yale Alcoholism Research Center, VA Medical Center, West Haven, CT 06516, USA.
Compere
S
S
Nestler
E J
EJ
Rasmussen
K
K
D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004594:Electrophysiology; D008125:Locus Coeruleus / Q000187:drug effects / Q000502:physiology*; D008297:Male; D009021:Morphine Dependence / Q000523:psychology*; D009271:Naltrexone / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology*; D009553:Nimodipine / Q000494:pharmacology*; D009638:Norepinephrine / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013375:Substance Withdrawal Syndrome / Q000523:psychology*
D002121:Calcium Channel Blockers; D009292:Narcotic Antagonists; D009553:Nimodipine; D009271:Naltrexone; D009638:Norepinephrine