Borgundvaag B, George S R
Life Sci. 1985 Jul 29;37(4):379-86. doi: 10.1016/0024-3205(85)90509-0.
The diterpenoid forskolin stimulated adenylate cyclase activity (measured by conversion of [3H]-ATP to [3H]-cAMP) in anterior pituitary from male and female rats. Inhibition of stimulated adenylate cyclase activity by potent dopaminergic agonists was demonstrable only in female anterior pituitary. The inhibition of adenylate cyclase activity displayed a typically dopaminergic rank order of agonist potencies and could be completely reversed by a specific dopamine receptor antagonist. The IC50 values of dopamine agonist inhibition of adenylate cyclase activity correlated with equal molarity with the dissociation constant of the high-affinity dopamine agonist-detected receptor binding site and with the IC50 values for inhibition of prolactin secretion. These findings support the hypothesis that it is the high-affinity form of the D2 dopamine receptor in anterior pituitary which is responsible for mediating the dopaminergic function of attenuating adenylate cyclase activity.
二萜类化合物福斯高林可刺激雄性和雌性大鼠垂体前叶中的腺苷酸环化酶活性（通过将[3H]-ATP转化为[3H]-cAMP来测定）。强效多巴胺能激动剂对刺激的腺苷酸环化酶活性的抑制作用仅在雌性垂体前叶中得到证实。腺苷酸环化酶活性的抑制表现出典型的多巴胺能激动剂效力等级顺序，并且可以被特异性多巴胺受体拮抗剂完全逆转。多巴胺激动剂抑制腺苷酸环化酶活性的IC50值与高亲和力多巴胺激动剂检测到的受体结合位点的解离常数以及抑制催乳素分泌的IC50值呈等摩尔相关。这些发现支持了这样一种假说，即垂体前叶中D2多巴胺受体的高亲和力形式负责介导减弱腺苷酸环化酶活性的多巴胺能功能。
