Abstract
Earlier reports had shown a profound effect of the below sea level environment of the Jordan Valley (JV) on serum levels of sex hormones in humans including testosterone (T). This effect was suggested to be clue to the environmental factors of higher temperatures and higher barometric pressure of the JV compared to those factors in areas above sea level such as Irbid City (IC).
Methods. Herein, two groups of eight male Sprague Dawley rats were selected from all litters obtained at our Animal Facility at the Jordan University of Science and Technology. The two groups were subdivided between IC and the JV.
Results. Adrenocortical cytochromes P-450 of the steroidogeneic pathways were higher in rats of both sexes growing in the JV compared to those maturing in IC. Intratesticular T levels were significantly higher in male rats growing in the JV than in those of the IC (638.262+/-18.2464 ng / mL compared to 434.108+/-22.3764 ng / mL).
Conclusion. The high blood levels of T in rats of the JV compared to those of IC are due not only to the high testicular production of T, but also to the higher activities of the adrenocortical cytochromes P-450 in rats growing at the JV.