Röjdmark S, Andersson D E, Sundblad L
J Clin Endocrinol Metab. 1981 Sep;53(3):594-8. doi: 10.1210/jcem-53-3-594.
The significance of calcium for the responsiveness of human lactotrophs and somatotrophs to iv TRH and oral L-dopa was investigated in 11 young healthy women. Both TRH and L-dopa were administered on three different background infusions: 1) saline, 2) verapamil, and 3) calcium. Twenty-five micrograms of TRH raised the PRL level from 15.1 +/- 2.3 to 76.9 +/- 8.8 ng/ml in 15 min (P less than 0.001). Calcium infusion blunted this PRL response by 33 +/- 8% (P less than 0.02), whereas verapamil, known for its calcium-antagonistic properties, left in unaffected. Five hundred milligrams of L-dopa increased the GH level from 2.2 +/- 0.7 to 16.7 +/- 2.2 ng/ml in 60 min (P less than 0.002) and reduced the PRL level from 11.6 +/- 2.9 to 3.1 +/- 0.4 ng/ml in 150 min (P less than 0.05). Neither calcium nor verapamil influenced these GH and PRL responses significantly. These findings indicate that human somatotrophs may be less dependent than human lactotrophs on normocalcemia for adequate hormone secretion.
在11名年轻健康女性中研究了钙对人催乳素细胞和生长激素细胞对静脉注射促甲状腺激素释放激素（TRH）和口服左旋多巴反应性的影响。TRH和左旋多巴均在三种不同的背景输注下给药：1）生理盐水，2）维拉帕米，3）钙。25微克TRH在15分钟内使催乳素水平从15.1±2.3 ng/ml升至76.9±8.8 ng/ml（P<0.001）。钙输注使这种催乳素反应减弱了33±8%（P<0.02），而以其钙拮抗特性闻名的维拉帕米则未使其受到影响。500毫克左旋多巴在60分钟内使生长激素水平从2.2±0.7 ng/ml升至16.7±2.2 ng/ml（P<0.002），并在150分钟内使催乳素水平从11.6±2.9 ng/ml降至3.1±0.4 ng/ml（P<0.05）。钙和维拉帕米均未对这些生长激素和催乳素反应产生显著影响。这些发现表明，人生长激素细胞在充足激素分泌方面可能比人催乳素细胞对正常血钙水平的依赖性更小。
