Testosterone to estrogen conversion is not responsible for the vasodilating effects of testosterone ex vivo.

Testosterone to estrogen conversion is not responsible for the vasodilating effects of testosterone ex vivo. Cell Mol Biol (Noisy-le-grand). 2018 Jan 31;64(1):111-117 Authors: Tan S, Yi D, Zhu W, Sun R, Wei M Abstract Men have a higher incidence of cardiovascular disease, but poorer vasodilatation than women. However, testosterone exerts vasodilating actions ex vivo. We aimed to determine if reactive oxygen species (ROS) produced in vivo could cause 'eNOS uncoupling' that accounts for the disparity between in vivo and ex vivo results. Ovariectomized SHR and WKY rats were divided into 3 groups: untreated, estradiol benzoate (EB) treated, and testosterone propionate (TP) treated. EB and TP rats were treated for 8 weeks, and blood pressure, serum estrogen, progesterone, and testosterone were measured. Rats were euthanized and aorta samples were taken for examination of nitric oxide, phosphorylated eNOS (p-eNOS), H2O2, gr91phos, and pAkt. Mesenteric arterial rings were used in myographic studies of endothelium dependent and independent vasorelaxation. The influence of testosterone added to the bathing solution of rings from testosterone-supplemented rats with/without an eNOS inhibitor, with/without blockade of androgen or estrogen receptors, and with/without an inhibitor of gp91phox was examined. Treatment with testosterone for 8 weeks did not change endothelium-dependent relaxation in response to acetylcholine in the presence or absence...
Source: Cellular and Molecular Biology - Category: Molecular Biology Tags: Cell Mol Biol (Noisy-le-grand) Source Type: research