Altered glucose kinetics in diabetic rats during gram-negative infection.

Abstract

The present study examined the purported exacerbating effect of sepsis on glucose metabolism in diabetes. Diabetes was induced in rats by an intravenous injection of 70 or 45 mg/kg streptozotocin. The higher dose produced "severe" diabetes, whereas the lower dose of streptozotocin produced a milder, "latent" diabetes. After a chronic diabetic state had developed for 4 wk, rats had catheters implanted and sepsis induced by intraperitoneal injections of live Escherichia coli. After 24 h of sepsis the blood glucose concentration was unchanged in nondiabetics and latent diabetics, but glucose decreased from 15 to 8 mM in the septic severe diabetic group. This decrease in blood glucose was not accompanied by alterations in the plasma insulin concentration. Glucose turnover, assessed by the constant intravenous infusion of [6-3H]- and [U-14C]glucose, was elevated in the severe diabetic group, compared with either latent diabetics or nondiabetics. Induction of sepsis produced a slight decrease in the glucose turnover in the severe diabetic group but did not alter turnover in the latent diabetics. The rate of glucose disappearance, used to quantitate the alterations in plasma glucose after an intravenous glucose tolerance test, was decreased in both groups of diabetics and was proportional to the severity of the diabetic state. Sepsis increased the rate of glucose disappearance in nondiabetic rats but had no effect in either group of diabetic animals. Sepsis also failed to alter the insulinogenic index, used to estimate the insulin secretory capacity, in diabetic rats.(ABSTRACT TRUNCATED AT 250 WORDS)