Involvement of the nucleus accumbens in the myorelaxant effect of baclofen in rats.
The study was designed to search for brain structures responsible for the myorelaxant action of baclofen. Rats were chronically implanted with cannulae in the medial nucleus accumbens (NAS). The muscle tone was increased by reserpine (10 mg/kg i.p.) and measured as a resistance of the hind foot, developed in response to successive passive bendings and straightenings in the ankle joint. (+/-)Baclofen (1 or 2.5 mg/0.5 microliter), injected bilaterally into the NAS 1.5 h after pretreatment with reserpine, decreased the muscle tone of flexors and extensors enhanced by that compound. It is suggested that GABAB receptors of the NAS are involved in the myorelaxant action of baclofen.
Lorenc-Koci
E
E
Department of Neuro-Psychopharmacology, Polish Academy of Sciences, Kraków.
Ossowska
K
K
Wardas
J
J
Konieczny
J
J
Wolfarth
S
S
D000818:Animals; D001418:Baclofen / Q000008:administration & dosage / Q000494:pharmacology*; D007267:Injections; D008297:Male; D009125:Muscle Relaxants, Central / Q000494:pharmacology*; D009129:Muscle Tonus / Q000502:physiology; D009132:Muscles / Q000187:drug effects / Q000502:physiology; D009714:Nucleus Accumbens / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D018080:Receptors, GABA-B / Q000187:drug effects / Q000378:metabolism; D012110:Reserpine / Q000494:pharmacology
D009125:Muscle Relaxants, Central; D018080:Receptors, GABA-B; D012110:Reserpine; D001418:Baclofen