[Influence of acute hyperinsulinism on arterial pressure of diabetics. Reproducibility of the hypotensive effect].

We have observed effects of acute hyperinsulinaemia on arterial pressure of five diabetics and tested the reproducibility of this action. Systolic (TAS) and diastolic (TAD) arterial pressure were studied during two hyperinsulinaemic-euglycaemic clamps effected with Artificial Pancreas (Biostator CGIIS, Miles) at one month of interval. During the first clamp, between the beginning of insulin infusion and the end of 4th stage, we have observed a fall of TAS (115 +/- 4, VS 137 +/- 6 mmHg; moy +/- SEM; p less than 0.05) and in less degree of TAD (76 +/- 2, VS 86 +/- 4 mmHg; NS). These modifications of arterial pressure were associated with no changes of heart rate and urinary sodium flow. On the other hand, we have observed a fall of serum levels of sodium (139 +/- 1, VS 141 +/- 1 mEq/l; p less than 0.05), urea (0.20 +/- 0.01, VS 0.32 +/- 0.02 g/l; p less than 0.001) whereas, balance-sheet of water was positive (+445 +/- 338 ml) at the end of clamp. During the second clamp, the fall of pressure has been reproducible, relating to the TAS (123 +/- 5, VS 145 +/- 4 mmHg; p less than 0.01) and non significantly to the TAD (78 +/- 2, VS 88 +/- 5 mmHg; NS). During the two tests, the mean of tension fall was identical (22 +/- 6 mmHg during first clamp, 22 +/- 4 mmHg during second one). So, acute hyperinsulinaemia induces a fall of arterial pressure, probably in bringing an influence on arterial vasodilatation since heart rate and urinary sodium excretion are unchanged and water balance-sheet is positive.(ABSTRACT TRUNCATED AT 250 WORDS)