The present study was undertaken to study the effects of chronic treatment with lisinopril on the cardiovascular complications in streptozotocin (STZ) diabetic and deoxycorticosteroneacetate (DOCA) hypertensive rats. Injection of STZ produced severe glycosuria (> 2%), hyperglycemia, hypoinsulnaemia, polydypsia, polyphagia and loss of body weight. It also produced hypothyroidism, hypercholesterolaemia, hypertriglyceridaemia, hypertension, bradycardia and decreased left ventricular developed pressure (LVDP). Elevation in serum creatinine level and increased activity of liver enzymes were also found in STZ treated animals. DOCA by itself did not produce any change in blood glucose but reduced serum insulin levels in non-diabetic animals. However, in the diabetic group, DOCA reduced blood sugar levels. Treatment of STZ-diabetic rats with DOCA did not aggravate cardiac depression or hyperglycaemia. Treatment of rats with lisinopril (1 mg kg-1, p.o. daily for six weeks), in diabetic and diabetic hypertensive animals prevented STZ induced loss of body weight and hypertension, bradycardia and hypothyroidism. It also prevented STZ induced hyperglycemia and hypoinsulinaemia in both diabetic and diabetic hypertensive animals. There was a reduction in cholesterol, triglyceride, and LDL levels; the ratio between total cholesterol to HDL and LDL to HDL and an improvement in LVDP at higher filling pressure in diabetic as well as diabetic hypertensive animals. Treatment with lisinopril also prevented hypertrophy and elevated levels of serum creatinine, SGOT and SGPT in diabetic animals. In conclusion, the present data suggests that STZ-DOCA model may not be considered as the ideal model for the study of cardiovascular complications of combined treatment hypertension and diabetes. However, the present investigation presents a number of beneficial effects of lisinopril treatment in diabetic with or without hypertensive rats and it may be considered as one of the drugs of choice in treatment of hypertension when it is associated with diabetes mellitus.

Angiotensin-Converting Enzyme Inhibitors↗

PubMedDate not supplied

Effect of chromium picolinate on histopathological alterations in STZ and neonatal STZ diabetic rats.

Earlier studies from our laboratory have indicated insulin sensitizing action of chromium picolinate as the mechanism of its anti-diabetic activity in experimental models of type I and type II diabetes. In the present investigation, we have evaluated the effects of chronic administration of chromium picolinate on the functional and histological alterations of streptozotocin (STZ)-induced diabetes in rats. Type I diabetes was induced by intravenous injection of STZ (40 mg/kg) in adult rats, whereas, type II diabetes was induced by intraperitoneal injection of STZ (90 mg/kg) in 2-day old rat pups which in adulthood develop abnormalities resembling type II diabetes. Chromium picolinate was administered at 8 microg/ml in drinking water for 6 weeks and was found to improve glucose tolerance and increase insulin sensitivity of STZ-diabetic rats. This treatment decrease elevated serum creatinine and urea levels as well as elevated serum levels of hepatic enzymes of both groups of diabetic rats. Histopathological studies of kidney and liver show decrease in the intensity and incidence of vacuolations, cellular infiltration and hypertrophy of STZ and nSTZ (neonatal STZ) diabetic rats. Chronic treatment with chromium picolinate however, did not alter the normal function or morphology of control rats. Chronic chromium picolinate at the therapeutic doses that improved glucose tolerance, was observed to have no hepatotoxic or nephrotoxic potential. It was rather found to improve renal and hepatic function and to reduce abnormalities associated with STZ-diabetes. Chromium picolinate could play an important role in the long term management of diabetes mellitus.

Animals↗