METABOLIC AND CIRCULATORY EFFECTS OF ORAL SALBUTAMOL IN THE THIRD TRIMESTER OF PREGNANCY IN DIABETIC AND NON-DIABETIC WOMEN

Summary Metabolic and cardiovascular effects of 4 mg oral salbutamol were studied in ten non-diabetic, ten chemical diabetic and five juvenile diabetic women in late pregnancy. None of the women had been treated with beta-sympathomimetic drugs earlier in their pregnancy. Heart rate and blood pressure were recorded and blood samples for measurement of plasma cyclic AMP, insulin, C-peptide, glucose, lactate, glycerol, non-esterified fatty acids (NEFA) and 3-hydroxybutyrate (3-HB) were collected every 30 minutes for 120 minutes after salbutamol. All women underwent the same procedure at random without salbutamol. There were significant cardiovascular effects of salbutamol in all the groups but no differences in these effects between the groups. Salbutamol caused significant increases of glycogenolysis and lipolysis in all the groups, significantly larger in the juvenile diabetic than the non-diabetic and chemical diabetic women. This observation could be explained by the inability of the juvenile diabetics to secrete insulin, shown by their non-measurable plasma C-peptide levels. The metabolic responses following salbutamol in the chemical diabetics were intermediate between the non-diabetic and juvenile diabetic groups. The results show that diabetes does not alter the sensitivity of beta-receptors involved in cardiovascular regulation, while the metabolic responses to oral salbutamol are enhanced, especially in juvenile diabetics. We suggest that during treatment with beta-sympathomimetic drugs, blood glucose should be monitored in all patients showing criteria of potential diabetes.