ABSTRACT
This study was designed to compare the plasma level of Endothelin - I and the arterial blood pressure in both normal and streptozotocin induced diabetic rats and to study the effect of insulin treatment on the two tested parameter in normal and diabetic rats. Sixty male rats were used and divided into 5 groups: group [1] [normal rats, served as control A], Group 2 [normal rats treated with insulin for 8 weeks], group 3 [diabetic rats served as control B],Group 4 [diabetic rats treated with insulin for 4 weeks] and Group 5 [diabetic rats treated with insulin for 8 week]. Our results showed that the mean arterial blood pressure was significantly decrease in diabetic rats, while their plasma level of Endothelin- I was higher than the non diabetic rats. Insulin administration to normal and diabetic rats produced significant rise in both tested parameters