DOPAMINE RECEPTOR BLOCKADE IN NUCLEUS-ACCUMBENS OR CAUDATE-NUCLEUS DIFFERENTIALLY AFFECTS FEEDING INDUCED BY 8-OH-DPAT INJECTED INTO DORSAL OR MEDIAN RAPHE

被引:69
作者
FLETCHER, PJ
机构
[1] Section of Biopsychology, Clarke Institute of Psychiatry, Toronto, Ont.
基金
英国医学研究理事会;
关键词
5-HYDROXYTRYPTAMINE; DOPAMINE; 8-HYDROXY-2-(DI-NORMAL-PROPYLAMINO)TETRALIN; ALPHA-FLUPENTIXOL; RAPHE; NUCLEUS ACCUMBENS; CAUDATE; FEEDING;
D O I
10.1016/0006-8993(91)90082-7
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
The 5-hydroxytryptamine (5-HT)1A receptor agonist 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) elicits a variety of behaviours including feeding in rats. These effects are accompanied by a reduction in 5-HT neurotransmission resulting from activation of somatodendritic 5-HT receptors located in the midbrain raphe nuclei. Previous work showing that dopamine receptor antagonists attenuate 8-OH-DPAT-induced feeding indicates that a facilitation of dopamine activity, secondary to reduced 5-HT activity, is involved in the expression of this effect. Microinjection studies were conducted to explore further the nature of this 5-HT-dopamine interaction. Injection of 8-OH-DPAT (0.125-2-mu-g) into either dorsal or median raphe induced dose-dependent increases in 1 h food intake in non-deprived rats. Pretreatment with haloperidol (0.05 and 0.1 mg/kg s.c.) attenuated the effect induced by median raphe 8-OH-DPAT (0.5-mu-g) complementing previous results with dorsal raphe 8-OH-DPAT. The feeding resulting from dorsal raphe (1-mu-g) or median raphe (0.5-mu-g) 8-OH-DPAT was attenuated by alpha-flupenthixol (1.25 and 2.5-mu-g) injected into the nucleus accumbens. alpha-Flupenthixol in either the dorsolateral or ventrolateral aspects of the caudate nucleus attenuated also the feeding response to dorsal raphe, but not median raphe, 8-OH-DPAT. However, alpha-flupenthixol in the dorsomedial caudate failed to alter feeding resulting from dorsal raphe 8-OH-DPAT. The results confirm the involvement of dopamine in mediating the effects on feeding 8-OH-DPAT and suggest that overlapping but different mechanisms are involved in the expression of the feeding resulting from dorsal and median raphe injection of 8-OH-DPAT. Thus, while the nucleus accumbens appears to be involved in both effects, the caudate nucleus is involved only in the effect derived from the dorsal raphe. The nucleus accumbens has been implicated in reward processes, whereas dopamine in the lateral caudate appears to facilitate sensorimotor integration. It is possible that these processes may underlie 8-OH-DPAT feeding. In a broader context these results may have important implications for understanding the diversity of motivated behaviours which can be elicited by 8-OH-DPAT and a reduction in 5-HT function.
引用
收藏
页码:181 / 189
页数:9
相关论文
共 47 条
[1]   SUPPRESSION OF EXPLORATORY LOCOMOTOR-ACTIVITY AND INCREASE IN DOPAMINE TURNOVER FOLLOWING THE LOCAL APPLICATION OF CIS-FLUPENTIXOL INTO LIMBIC PROJECTION AREAS OF THE RAT STRIATUM [J].
AHLENIUS, S ;
HILLEGAART, V ;
THORELL, G ;
MAGNUSSON, O ;
FOWLER, CJ .
BRAIN RESEARCH, 1987, 402 (01) :131-138
[3]  
AZAMI J, 1980, J PHYSL, V305, P18
[4]  
AZMITIA EC, 1978, HDB PSYCHOPHARMACOLO, V9
[5]   8-HYDROXY-2-(DI-NORMAL-PROPYLAMINO)TETRALIN(8-OH-DPAT) ELICITS EATING IN FREE-FEEDING RATS BY ACTING ON CENTRAL SEROTONIN NEURONS [J].
BENDOTTI, C ;
SAMANIN, R .
EUROPEAN JOURNAL OF PHARMACOLOGY, 1986, 121 (01) :147-150
[6]   POTENTIAL ANXIOLYTIC PROPERTIES OF 8-HYDROXY-2-(DI-N-PROPYLAMINO)TETRALIN, A SELECTIVE SEROTONIN1A RECEPTOR AGONIST [J].
CARLI, M ;
SAMANIN, R .
PSYCHOPHARMACOLOGY, 1988, 94 (01) :84-91
[7]   DIFFERENTIAL EFFECTS OF CENTRAL SEROTONIN MANIPULATION ON HYPERACTIVE AND STEREOTYPED BEHAVIOR [J].
CARTER, CJ ;
PYCOCK, CJ .
LIFE SCIENCES, 1978, 23 (09) :953-960
[8]   8-HYDROXY-2-(DI-N-PROPYLAMINO)TETRALIN, A SELECTIVE SEROTONIN1A RECEPTOR AGONIST, REDUCES THE IMMOBILITY OF RATS IN THE FORCED SWIMMING TEST BY ACTING ON THE NUCLEUS RAPHE DORSALIS [J].
CERVO, L ;
GRIGNASCHI, G ;
SAMANIN, R .
EUROPEAN JOURNAL OF PHARMACOLOGY, 1988, 158 (1-2) :53-59
[9]  
DAVIES M, 1989, Society for Neuroscience Abstracts, V15, P553
[10]  
DEBELLEROCHE J, 1982, J NEURAL TRANSM, V55, P923