Fuenmayor L D, Bermúdez M
J Neurochem. 1985 Mar;44(3):670-4. doi: 10.1111/j.1471-4159.1985.tb12866.x.
The effect of the cerebral 5-hydroxytryptamine system on the turnover of striatal 3,4-dihydroxyphenyl-ethylamine (dopamine) was investigated by measuring the level of dopamine and one of its metabolites in rats depleted of cerebral 5-hydroxytryptamine or treated with a 5-hydroxytryptamine receptor blocker. Treatment with p-chlorophenylalanine induced, in addition to a reduction in striatal 5-hydroxytryptamine and 5-hydroxyindol-3-ylacetic acid, an increase in the striatal concentration of dopamine, a diminution in the concentration of homovanillic acid in the same cerebral area, and a reduction in the rise of this acid after the administration of a butyrophenone derivative or tetrabenazine. Treatment with methysergide also reduced the increase of homovanillic acid induced by the butyrophenone. When probenecid was given to rats treated with p-chlorophenylalanine, homovanillic acid failed to accumulate, whereas the accumulation of 5-hydroxyindol-3-ylacetic acid was unaffected. The decay of dopamine after alpha-methyl-p-tyrosine administration was normal for the first 6 h but was later reduced in rats given p-chlorophenylalanine or methysergide. The results suggest that the lack of activation of 5-hydroxytryptamine receptors leads to a reduction in the turnover of dopamine in the nigrostriatal pathway.
通过测量脑内5-羟色胺耗竭或用5-羟色胺受体阻滞剂处理的大鼠体内多巴胺及其一种代谢产物的水平，研究了脑内5-羟色胺系统对纹状体3,4-二羟基苯乙胺（多巴胺）周转的影响。对大鼠用对氯苯丙氨酸处理后，除了纹状体5-羟色胺和5-羟吲哚-3-乙酸减少外，纹状体多巴胺浓度增加，同一脑区高香草酸浓度降低，给予丁酰苯衍生物或丁苯那嗪后该酸的升高也减少。用麦角新碱处理也减少了丁酰苯诱导的高香草酸增加。当丙磺舒给予用对氯苯丙氨酸处理的大鼠时，高香草酸未能积累，而5-羟吲哚-3-乙酸的积累未受影响。给予α-甲基-对酪氨酸后，多巴胺在前6小时的衰减正常，但在用对氯苯丙氨酸或麦角新碱处理的大鼠中，随后衰减减少。结果表明，5-羟色胺受体缺乏激活导致黑质纹状体通路中多巴胺周转减少。
