The metabolic clearance rate (MCR) of radio-labeled growth hormone (GH) was measured in eleven recently diagnosed patients with juvenile-onset diabetes mellitus and in seven healthy nonhospitalized healthy children. The patients with diabetes mellitus demonstrated a significant reduction in MCR of GH as compared to the contrast group. Peripheral GH levels did not reach steady state conditions in the patients with diabetes, thus pituitary production rates of GH could not be evaluated in these patients. It is suggested that diabetes mellitus, even in its earliest clinically apparent stages is associated with a defect in the metabolic clearance of GH. Since the liver has been demonstrated to be the major organ responsible for GH clearance in man, it is evident that diabetes mellitus may be associated with a defect in the hepatic clearance mechanisms for growth hormone. DIABETES 21: 115-11, March, 1972. Although the diabetogenic effects of growth hormone (GH) in man have been clearly demonstrated, the role of this hormone in the pathogenesis and complications of human diabetes mellitus remains unclear. Plasma concentrations of GH have been extensively evaluated in patients with diabetes. The basal plasma GH concentrations and the responses following provocative testing in adult diabetics do not generally differ from control subjects. 1 ' 4 In contrast, studies in the prediabetic and juvenile diabetic patient have suggested the presence of elevated GH levels following tolbutamide adminstration, 5 during the twenty-four-hour day 6 and in response to exercise. 7 These observations have been interpreted to indicate that pituitary GH release is increased in diabetes mellitus. Elevated plasma GH levels alone do not permit distinction, however, between enhanced

A highly sensitive method utilizing competitive protein binding was used to study concentrations of progesterone in the plasma of mothers, in umbilical cord plasma, and in the plasma of full-term and premature infants in the immediate postpartum period.Blood samples were obtained from 20 mothers during labor and from the cords of their infants at delivery. Most of these infants were also studied at 2 or 3 days of age. For purposes of comparison, a second series of samples was obtained from control subjects using needle aspiration to obtain samples from the umbilicus; 14 samples were studied.In the mothers, concentrations of progesterone in plasma ranged from 46 to 387 ng/ml (mean: 129±78 SD) ; in cord blood, progesterone levels ranged from 440 to 2,000 ng/ml (mean: l,030±412 SD); and in blood from the umbilical vein, concentrations of progesterone ranged from 310 to 720 ng/ml (mean: 562±140 SD).A total of 27 full-term newborns was studied at 24, 48, and 72 h of life. In four cases, blood was obtained from the same infant at 12, 24, and 72 h of life. The highest concentrations of progesterone were noted during the first 24 h of life, with levels ranging from 13 to 32 ng/ml (mean: 19 ng/ml) at 12 h, and from 2 to 32 ng/ml (mean: 16 ng/ml) at 24 h. By day 2, levels of progesterone had decreased to 3-20 ng/ml (mean: 10 ng/ml) and by day 3 were reduced to 0-16 ng/ml (mean: 8 ng/ml).Thirty-two premature infants, with birth weights of from 1,317 to 2,465 g, and ranging in gestational age from 30 to 40 weeks, were also studied. In several cases serial blood samples were obtained by the same methods used with the full-term infants. Two sets of twins were included. In premature infants, as with full-term newborns, a range of 4-34 ng/ml (mean: 14 ng/ml) was found at 12 h of life, decreasing rapidly to 2-6 ng/ml (mean: 3 ng/ml) by 24 h of life. These low concentrations persisted throughout days 2 and 3.There was no significant difference between concentrations of progesterone in plasma in full-term and premature infants at 2-3 days of age. It appeared that premature infants were as able to clear progesterone from the plasma as were the full-term infants. SpeculationThe data obtained in this study support the concept that large amounts of progesterone are delivered from the placenta to the fetus. This compound may be a precursor of C-21 steroids such as cortisol, synthesized by the fetal adrenal. Progesterone has also been shown to effect respiration in animals GONLY, MORRISON, SANDBERG and CLEVELAND 77and man [7,8,14,15] and an effect on neonatal respiratory mechanisms and disease may occur, although this has not been demonstrated.Maternal blood has a relatively large concentration of progesterone which diminishes rapidly following delivery of the placenta. Presumably the compound exerts some effect in the maintenance of pregnancy. Its exact role has not been established.

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