Protective effects of melatonin, vitamin e, vitamin c and their combinations on chronic lead-induced hypertensive rats

Abstract EN

The aim of the present study was to investigate the effects of long-term administration of melatonin, vitamin C, vitamin E and their combinations, on blood pressure, serum nitric oxide (NO ),calcium ions and electrolytes in lead-induced hypertensive rats .

Fifty four adult female albino rats were used in this study.

The experimental rats were divided to nine groups, each of six individuals and the treatments were continued for 10 weeks as the following: Group 1: Control rats.

Group 2: Sodium acetate (0.1mg/L drinking water).

Group 3: Lead acetate (Pb).

(0.1mg/L drinking water) Group 4: Pb + Melatonin.

(60 mg of melatonin/kg diet) Group 5: Pb + Vitamin E.

(1000 I.U of vitamin E /kg diet) ,(Group 6: Pb +Vitamin C (1mg of vitamin C/L drinking water).

Group 7 (Combination ): Pb +Melatonin + Vitamin E ,Group 8 (Combination ): Pb + Melatonin +Vitamin C , and Group 9 ( Combination ): Pb +Vitamin E+ Vitamin C.

A significant rise in systolic blood pressure (SBP) was noted 10 weeks after the onset of lead exposure in the Pb group.

Administration of melatonin or vitamin c significantly reduced SBP on fourth week of treatments , whereas vitamin E caused a reduction in SBP on the sixth of treatments.

Interestingly, melatonin in combination with vitamin E or C reduced SBP statistically more than vitamin E or C or their combinations.

Co-administration of melatonin and vitamin E caused a significant decrease in heart rate on the eighth weeks of treatments.

Reduction of serum NO that were detected in Pb treated rats were improved by melatonin, vitamin C, vitamin E and their combinations.

Serum calcium was decreased in Pb treated rats , whereas serum sodium and potassium did not change.

There were no statistical changes in body weight and food intake among the studied groups.