Plasma prolactin in juvenile diabetics. 24-h studies with somatostatin

In normal subjects during 24-hours saline infusion, plasma prolactin showed a number of small rises during day and night. The mean night-time level was significantly higher than the day-time level (8.2 +/- 0.6 ng/ml as against 4.7 +/- 0.5 ng/ml). In 12 insulin-dependent diabetics the 24 h plasma prolactin pattern was identical to that found in normals. Somatostatin infusion (4 mg/24 h in normals; 2--6 mg/24 h in diabetics) had no effect on the 24 h plasma prolactin pattern in either normals or in diabetics.