Low-dose streptozotocin-induced diabetes in the spontaneously hypertensive rat

Abstract

Streptozotocin (STZ, 35 mg/kg body weight) was injected into spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats, and plasma glucose and triglyceride concentrations measured 10 days later. Neither mean (±SEM) plasma glucose (130 ± 3 v 136 ± 3 mg/dL) nor triglyceride (93 ± 6 v 108 ± 7 mg/dL) concentrations increased in WKY rats. In contrast, both plasma glucose (141 ± 3 v 262 ± 36) and triglyceride (121 ± 8 v 196 ± 7 mg/dL) concentrations increased significantly ( P < .01) following administration of STZ in SHR. Furthermore, when SHR previously injected with STZ were fed a diet enriched in fructose, they had a further increase ( P < .01) in both plasma glucose (343 ± 38 mg/dL) and triglyceride (774 ± 57 mg/dL) concentrations. Plasma triglyceride concentration also increased significantly ( P < .05) when STZ-injected WKY rats ingested the fructose-enriched diet, but plasma glucose levels still remained within the normal range (152 ± 5 mg/dL). These results indicate that SHR were more sensitive to the effects of a decrease in pancreatic β-cell function (STZ) and an increase in insulin resistance (fructose feeding) than WKY rats.