Effect of hypothyroidism on Zinc and Copper levels of seminal plasma in rats

Thyroid hormones play a role in cell growth regulation, metabolism, and body trace elements. These hormones, copper and zinc are effective on fertility. The aim of this study was to evaluate the effect of thyroid function on the amount of copper and zinc in rat seminal plasma.

Twenty four male Wistar rats divided in 3 groups (n = 8) including: control group, hypothyroid groups which treated by methimazole low dose (20 mg in 100 ml of drinking water) and which treated by methimazole high dose (100 mg in 100 ml of drinking water). At the end of a 42-day treatment period, blood samples were taken from animals under deep anesthesia. Serum samples were collected from blood, and semen plasma samples were collected from seminal vesicle. The body and testis of animal were weighted. Hematocrit (HCT) was determined. Serum levels of thyroxin hormone (T4) were measured by Radioimmunoassay. The content of the Copper (Cu) and Zinc (Zn) in the seminal plasma was determined with inductively coupled plasma optical emission spectrometry.

Methimazole decreased the serum T4 level (p < 0.001), Zn in the seminal plasma (p < 0.001) and relative weight of the testes (p < 0.01) in a significant and dose-dependent manner. Hematocrit level decreased in two hypothyroid groups (p < 0.001). The testis weight and Cu in the seminal plasma reduced in the high dose treatment group (p < 0.01).

Methimazole or hypothyroidism induced by methimazole attenuated zinc concentration in seminal plasma, testes relative weight and Hematocrit level. However, copper reduction in the seminal plasma occurred only by high dose of methimazole.