Testicular haemodynamics, plasma testosterone and oestradiol concentrations, and serum nitric oxide levels in the Egyptian buffalo bull after a single administration of human chorionic gonadotropin.

Abstract

This current study aimed for the first time to evaluate the effect of a single intravenous administration of human chorionic gonadotropin hormone (hCG) on the testicular artery haemodynamics measurements (resistance [RI], and pulsatility indices [PI]), plasma steroids (estradiol-17β and testosterone) and nitric oxide (NO) levels in buffalo bulls. Twelve Egyptian buffalo bulls weighted 450±20kg were randomly divided into the hCG group (n=6) and injected a single dose with Ovogest (EPIFASI; 5,000 IU, iv), whereas the others (n=6) were injected with normal saline and served as controls. Doppler evaluation and blood sampling were performed just before the administration (hour 0) and at 1, 2, 4, 6, 8, 10, 24 and 28hr after administration. Bulls in the control group did not show any alterations in hormonal levels and blood flow parameters (p>.05). In the hCG group, RI was declined (p<.05) in 6hr post-administration (0.31±0.01 versus 0.45±0.01), while PI was declined (p<.05) later in 10hr (0.74±0.01 versus 1.23±0.02). Additionally, testicular blood flow was increased (p<.05) 8hr (42.02±1.02ml/min/100g versus 31.34±0.88ml/min/100g) after administration. Testosterone and NO levels were (p<.05) increased at 4 and 6hr post-administration (3.55±0.03ng/ml versus 2.84±0.01ng/ml, and 55.32±4.25µmol/L versus 32.21±1.55µmol/L), whereas oestradiol levels were elevated (p<.05)in 6hr (31.25±0.08pg/ml) only post-administration then declined. In conclusion, the single intravenous administration of hCG triggered many alterations in the supratesticular artery vascularization and hormonal profile that could affect positively on steroidogenesis and testicular function in buffalo bull.