Laakso Aki, Vilkman Harry, Bergman J, Haaparanta Merja, Solin Olof, Syvälahti Erkka, Salokangas Raimo K R, Hietala Jarmo
Department of Pharmacology and Clinical Pharmacology, University of Turku, Finland.
Biol Psychiatry. 2002 Oct 1;52(7):759-63. doi: 10.1016/s0006-3223(02)01369-0.
There are sex differences in the clinical features of several neuropsychiatric illnesses associated with dopamine dysfunction. The effects of sex on brain dopaminergic function have been sparsely studied in human subjects using modern imaging techniques. We have previously reported that the apparent affinity of [(11)C]raclopride for striatal D(2) dopamine receptors in vivo is lower in women than in men, whereas D(2) receptor density is not different. This finding indirectly suggests that women have a higher synaptic concentration of dopamine in the striatum. We explored further the basis of this phenomenon in an independent study and hypothesized that striatal presynaptic dopamine synthesis capacity would also be elevated in women.
A total of 23 healthy men and 12 healthy women (age range 20-60 years) were studied using positron emission tomography and [(18)F]fluorodopa.
Women had significantly higher striatal [(18)F]fluorodopa uptake (Ki values) than men. The difference was more marked in the caudate (+26%) than in the putamen (+12%). In addition, there was a negative correlation between striatal [(18)F]fluorodopa Ki values and age in men but not in women.
The results further substantiate sex differences in striatal dopaminergic function in humans. This finding may be associated with sex differences in vulnerability and clinical course of neuropsychiatric disorders with dopaminergic dysregulation, e.g., schizophrenia, alcohol dependence, and Parkinson's disease.
几种与多巴胺功能障碍相关的神经精神疾病的临床特征存在性别差异。利用现代成像技术对人类受试者中性别对脑多巴胺能功能的影响进行的研究较少。我们之前报道过，[(11)C]雷氯必利在体内对纹状体D(2)多巴胺受体的表观亲和力在女性中低于男性，而D(2)受体密度并无差异。这一发现间接表明女性纹状体中多巴胺的突触浓度较高。我们在一项独立研究中进一步探究了这一现象的基础，并假设女性纹状体突触前多巴胺合成能力也会升高。
使用正电子发射断层扫描和[(18)F]氟多巴对23名健康男性和12名健康女性（年龄范围20 - 60岁）进行了研究。
女性纹状体[(18)F]氟多巴摄取（Ki值）显著高于男性。尾状核（+26%）的差异比壳核（+12%）更为明显。此外，男性纹状体[(18)F]氟多巴Ki值与年龄呈负相关，而女性则不然。
结果进一步证实了人类纹状体多巴胺能功能存在性别差异。这一发现可能与多巴胺调节异常的神经精神疾病（如精神分裂症、酒精依赖和帕金森病）在易感性和临床病程方面的性别差异有关。
