Piletz J E, Halaris A, Saran A, Marler M
Department of Psychiatry, Case Western Reserve University, Cleveland, Ohio.
Neuropsychopharmacology. 1990 Jun;3(3):201-10.
Purified platelet plasma membranes were used to compare 3H-para-aminoclonidine binding in 18 depressed patients and 24 sex- and age-matched, healthy control subjects. Two site-selective concentrations of the radioligand were used (0.06 and 1.5 nmol/L) to investigate two high-affinity 3H-para-aminoclonidine binding sites. Radioligand binding was significantly elevated in platelets of depressed patients at both concentrations of 3H-para-aminoclonidine whether expressed per milligram protein, per platelet, or per square micrometer of platelet surface area (each p less than 0.02). These data agree with most previous studies, suggesting that a subset of platelet alpha 2 adrenoceptors, recognized by clonidine and its derivative para-aminoclonidine, is upregulated in depressed patients. By using purified plasma membranes, our data rule out the possibility that an inhibitor may have masked receptor binding in previous studies which used total platelet lysates. The present findings thus support the alpha 2 adrenoceptor hypersensitivity theory of depression.
纯化的血小板质膜被用于比较18例抑郁症患者与24例性别和年龄匹配的健康对照者的3H-对氨基可乐定结合情况。使用两种位点选择性浓度的放射性配体（0.06和1.5 nmol/L）来研究两个高亲和力的3H-对氨基可乐定结合位点。无论以每毫克蛋白质、每个血小板还是每平方微米血小板表面积来表示，在两种浓度的3H-对氨基可乐定条件下，抑郁症患者血小板中的放射性配体结合均显著升高（每个p值均小于0.02）。这些数据与大多数先前的研究一致，表明可乐定及其衍生物对氨基可乐定所识别的血小板α2肾上腺素能受体的一个亚群在抑郁症患者中上调。通过使用纯化的质膜，我们的数据排除了在先前使用全血小板裂解物的研究中抑制剂可能掩盖受体结合的可能性。因此，目前的研究结果支持抑郁症的α2肾上腺素能受体超敏理论。
