[Behavior of C-peptide, insulin and glucose levels in blood during conditions of evaluating selected antihypertensive drugs in patients with hypertension and non-insulin-dependent diabetes (type 2)].

Unlabelled: In 60 patients divided in three groups, each of 10 non-diabetic patients with essential hypertension (h) and of 10 hypertensive type 2 (non-insulin-dependent) diabetics (h+c), aged 31-63 years, the effect of 2-week treatment with nifedipine, captopril and prazosin on glycaemia, serum insulin (IRI) and C peptide (CP) after oral and i.v. glucose loading was compared. Nifedipine resulted in higher glycaemia levels in the oral test in both groups. This drug caused in group (h), but not in group (h+c), reduction of the glucose-dependent early increases of serum IRI and CP, more marked in respect to CP, what was expressed by the decrease of the serum CP:IRI ratio. These results prove that in non-diabetic patients nifedipine reduces the early response of the B-cells to glucose, but this effect is partly compensated by decreased insulin uptake by the liver. In patients with type 2 diabetes this phenomenon has not become manifest because of absence or reduction of early glucose-dependent insulin release. After captopril in both groups lower values of glycaemia and serum IRI and CP were found. Prazosin did not change the determined blood parameters.

Conclusion: nifedipine, captopril, prazosin have a small influence on secretory function of pancreatic B-cells and may be recommended for the treatment of hypertension in patients with type 2 (non-insulin-dependent) diabetes.