Hypoglycaemic effect of short acting biosynthetic human and bovine insulin. A comparative study.

The aim of the study was to compare the strength of action, the timing of maximal effect and duration of hypoglycaemic effect of biosynthetic human insulin compared to conventional bovine short acting insulin. On that purpose, a modified insulin tolerance test was performed in 10 healthy persons, first with bovine (Kristalni Insulin-Galenika) and a week later, with a biosynthetic human (Bio.-Human Insulin-Lilly) insulin in a dose of 0.15 U/kg body weight. The blood samples for estimation of glycaemia (glucose oxidase method) were collected at 0, 5, 10, 15, 20, 25, 30, 40, 50, 60, 90 and 120 minutes. Comparing the degree of hypoglycaemia, the time of its beginning and its duration, it is concluded that there was no statistically significant difference between biosynthetic human and conventional short acting bovine insulin used in a single dose in healthy persons.

Effects of cytotoxic therapy on hypothalamic-pituitary-adrenal axis response to insulin-induced hypoglycemia in patients with a variety of acute leukemias.

The effect of cytotoxic therapy (including cytosine-arabinoside and thioguanine) on the adrenal response to insulin-induced hypoglycemia has been investigated in 15 newly diagnosed patients with an acute form of leukemia. Hypoglycemia was induced with crystalline insulin (0.15 U kg-1). Cortisol, growth hormone and prolactin were determined by radioimmunoassay at 0, 30, 60, 90 and 120 min during the insulin-tolerance test and also before and after the completion of the therapy. There was a significant impairment of a cortisol response after the completion of the cytotoxic therapy, while no significant changes could be detected in growth hormone and prolactin response. It is concluded that either cortisol synthesis or release mechanism was compromised by the cytotoxic therapy and/or metabolic derangements brought about therewith.

Chronic bromocriptine treatment and glucose intolerance in acromegaly.

Blood glucose, plasma GH, insulin and glucagon levels during OGTT before and after treatment with bromocriptine (20 - 40 mg daily 3 - 18 months) were studied in 12 nondiabetic acromegalics (NA) and 6 diabetic acromegalics (DA) not treated previously. There was no significant change in blood glucose levels before and after treatment in NA while blood glucose levels fell significantly in DA after treatment. Mean basal GH levels and after OGTT decreased significantly in NA group, while only in the 120 min of OGTT in DA group. There was no significant change in mean basal or glucose stimulated plasma insulin or glucagon levels before and after treatment in both non-diabetic and diabetic acromegalics. Normal glucagon levels in diabetic acromegalics prior to treatment is considered as relative hyperglucagonaemia which disappeared after treatment. We did not show that glucagon suppressibility after OGTT was reestablished after treatment with bromocriptine in non-diabetic and diabetic acromegalics. Other factors than changes in hormones should be considered as a cause of restored glucose tolerance.

Prolactin and growth hormone response in induced hypoglycaemia in obese patients.

Obesity represents a metabolic abnormality which brings a disordered hormone response during functional pituitary tests. Twenty obese patients were investigated and growth hormone and prolactin response during the insulin tolerance test were determined and the result was compared to an adequate control group consisting of 10 healthy nonobese patients. Two types of prolactin response were obtained--one normal and one decreased, unlike the growth hormone response which was constantly decreased. The authors discuss the hypothesis according to which the defect of endocrine hypothalamus might be an etiological factor of obesity.