Kaji H, Chihara K, Minamitani N, Kodama H, Kita T, Fujita T
Acta Endocrinol (Copenh). 1985 Mar;108(3):297-304. doi: 10.1530/acta.0.1080297.
The effect of [Asu1,7]eel calcitonin (ECT), an equipotent analogue of eel CT, on prolactin (Prl) secretion was examined in 12 healthy male subjects and in 6 patients with prolactinoma. In healthy subjects, ECT (0.5 microgram/kg body weight . h) or saline was infused for 2 h and TRH was injected iv as a bolus of 500 micrograms at 1 h of ECT or saline administration. ECT did not affect basal Prl levels during 1 h of infusion. TRH caused a significant increase of plasma Prl with peak values of 75.2 +/- 11.6 ng/ml in ECT-infused subjects, which did not differ from those infused with saline (68.5 +/- 8.3 ng/ml). Next, an iv bolus injection of regular insulin (0.1 U/kg body weight) was followed by an infusion of ECT or saline alone. Plasma Prl peaks after hypoglycaemic stress were significantly lower in ECT-infused subjects than those in saline-injected controls (ECT, 16.5 +/- 3.1 vs 33.5 +/- 9.6 ng/ml, P less than 0.05). In patients with prolactinoma, basal levels of plasma Prl ranging from 42.0-4130 ng/ml failed to change during iv infusion of ECT. Moreover, ECT (10(-9) - 10(-6)M) did not affect Prl release from prolactinoma tissues perifused in vitro. These findings suggest that ECT may not act directly on the pituitary to modify Prl release. Rather, peripherally administered ECT appears to suppress Prl release via the central nervous system.
在12名健康男性受试者和6名催乳素瘤患者中，研究了鳗鱼降钙素（ECT）的等效类似物[Asu1,7]鳗鱼降钙素对催乳素（Prl）分泌的影响。在健康受试者中，以0.5微克/千克体重·小时的剂量输注ECT或生理盐水2小时，并在输注ECT或生理盐水1小时时静脉推注500微克促甲状腺激素释放激素（TRH）。在输注1小时期间，ECT不影响基础Prl水平。TRH使输注ECT的受试者血浆Prl显著升高，峰值为75.2±11.6纳克/毫升，与输注生理盐水的受试者（68.5±8.3纳克/毫升）无差异。接下来，静脉推注常规胰岛素（0.1单位/千克体重），然后单独输注ECT或生理盐水。低血糖应激后，输注ECT的受试者血浆Prl峰值显著低于注射生理盐水的对照组（ECT为16.5±3.1纳克/毫升，对照组为33.5±9.6纳克/毫升，P<0.05）。在催乳素瘤患者中，静脉输注ECT期间，血浆Prl基础水平在42.0 - 4130纳克/毫升范围内未发生变化。此外，ECT（10⁻⁹ - 10⁻⁶摩尔/升）不影响体外灌流的催乳素瘤组织释放Prl。这些发现表明，ECT可能不会直接作用于垂体来改变Prl释放。相反，外周给予的ECT似乎通过中枢神经系统抑制Prl释放。
