EFFECT OF RITODRINE ON CARBOHYDRATE AND LIPID-METABOLISM IN NORMAL AND DIABETIC PREGNANT-WOMEN

The metabolic effects of a one hour intravenous infusion of the β-2-receptor stimulating drug ritodrine were studied in seven normal pregnant women, three White class A pregnant diabetics and eight White class B-D pregnant diabetics. During ritodrine infusion all subjects in the three groups exhibited increases in plasma glucose (1.0, 1.6 and 2.1 mmol/l respectively), free fatty acids (360, 850 and 1150 μ/mol/l), lactate (0.43, 0.80 and 0.86 mmol/l) and β-hydroxybutyrate and decreases in standard bicarbonate. The rise in plasma glucose, free fatty acids and lactate was more pronounced in insulin treated diabetic. The rises in β-hydroxybutyrate and decreases in standard bicarbonate were of the same magnitude in all three groups. Plasma potassium fell in all subjects, whereas no detectable changes in plasma sodium were observed. The endocrine pancreatic function was assessed by measuring plasma insulin (white class A and normals), C-peptide (White class B-D) and glucagon (all subjects). Plasma insulin increased in normals (22 μIU/ml) aand White class A diabetics (33 μIU/ml), whereas plasma C-peptide of the insulin treated patients (White class B-D) were below measurable contractions. Plasma glucagon and cortisol concentrations were not influenced by ritodrine. The results suggest that the diabetogenic changes induced by ritodrine are augmented with the severity of diabetes but not ascribable to a diabetes-like change in the function of the endocrine pancreas.