TY - JOUR
T1 - Selective involvement of dopamine in the nucleus accumbens in the feeding response elicited by muscimol injection in the nucleus raphe dorsalis of sated rats
AU - Bendotti, C.
AU - Berettera, C.
AU - Invernizzi, R.
AU - Samanin, R.
PY - 1986
Y1 - 1986
N2 - Muscimol injection (100 ng) in the nucleus raphe dorsalis (NRD) caused intense eating in non-food-deprived rats. At a dose (10 μg) blocking dopamine mediated responses (examined by increased locomotion or stereotypy caused by systemically injected d-amphetamine), fluphenazine injected in the n. accumbens, but not in the striatum, significantly reduced the eating response elicited by muscimol in the NRD while food intake of deprived rats was not significantly modified by fluphenazine injected in either area. Fluphenazine (20 μg) in the striatum reduced eating in both conditions, but the animals showed marked sedation which obviously interfered with the feeding response. Dopamine release and synthesis, measured respectively by 3-methoxytryramine and accumulation of dihydroxyphenylalanine after aromatic amino acid decarboxylase inhibition, were significantly reduced in the n. accumbens, but not in the striatum, of muscimol treated animals. The metabolism of serotonin was reduced in both areas of muscimol treated rats. It is suggested that changes in dopamine receptor sensitivity, together with changes in serotonin function, might be involved in the feeding response caused by muscimol injection in the NRD.
AB - Muscimol injection (100 ng) in the nucleus raphe dorsalis (NRD) caused intense eating in non-food-deprived rats. At a dose (10 μg) blocking dopamine mediated responses (examined by increased locomotion or stereotypy caused by systemically injected d-amphetamine), fluphenazine injected in the n. accumbens, but not in the striatum, significantly reduced the eating response elicited by muscimol in the NRD while food intake of deprived rats was not significantly modified by fluphenazine injected in either area. Fluphenazine (20 μg) in the striatum reduced eating in both conditions, but the animals showed marked sedation which obviously interfered with the feeding response. Dopamine release and synthesis, measured respectively by 3-methoxytryramine and accumulation of dihydroxyphenylalanine after aromatic amino acid decarboxylase inhibition, were significantly reduced in the n. accumbens, but not in the striatum, of muscimol treated animals. The metabolism of serotonin was reduced in both areas of muscimol treated rats. It is suggested that changes in dopamine receptor sensitivity, together with changes in serotonin function, might be involved in the feeding response caused by muscimol injection in the NRD.
KW - Caudate putamen
KW - Dopamine
KW - Feeding behaviour
KW - Muscimol
KW - Nucleus accumbens
KW - Nucleus raphe dorsalis
UR - http://www.scopus.com/inward/record.url?scp=0022448381&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0022448381&partnerID=8YFLogxK
U2 - 10.1016/0091-3057(86)90169-3
DO - 10.1016/0091-3057(86)90169-3
M3 - Article
C2 - 2425377
AN - SCOPUS:0022448381
VL - 24
SP - 1189
EP - 1193
JO - Pharmacology Biochemistry and Behavior
JF - Pharmacology Biochemistry and Behavior
SN - 0091-3057
IS - 5
ER -