The effects of zinc deficiency and testosterone supplementation on leptin levels in castrated rats and their relation with LH, FSH and testosterone.

AIM

The aim of this study was to investigate how zinc-deficiency and testosterone supplementation, both in combination and individually, affect plasma LH, FSH and leptin levels in castrated rats.

DESIGN

Group 1, Control Group. Group 2, Castration Group. Group 3, Testosterone Group. Group 4, Zinc-deficient Group. Group 5, Testosterone, Zinc-deficient Group. Group 6, Zinc-deficient, Castration Group. Group 7, Testosterone, Castration Group. Group 8, Zinc-deficient, Testosterone, Castration Group.

MEASUREMENTS

Plasma zinc, leptin, LH, FSH, free and total testosterone levels were measured.

RESULTS

Group 2 had the highest levels of leptin and LH, besides having the highest FSH levels together with Group 6 (p<0.01). Groups 5 and 8 had the lowest leptin levels (p<0.01). Leptin levels in Groups 4 and 7 were higher than those in Groups 5 and 8, but lower than those in all other groups (p<0.01). LH levels in Group 4 were not different than those in Groups 3, 5 and 8, but significantly lower than those in all other groups (p<0.01). Free and total testosterone levels were higher in Group 4 than in castration groups that were not supplemented testosterone, but were lower in the former than in all others (p<0.01).

CONCLUSION

Plasma LH may be more effective than testosterone on plasma leptin and zinc can be an important mediator of the effect LH exercises on leptin.