Membrane testosterone receptors in cultured vascular smooth muscle cells / 中华男科学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To determine the presence of membrane testosterone receptors in cultured vascular smooth muscle cells (VSMC), and investigate their relationship with classical intracellular androgen receptors (iAR).</p><p><b>METHODS</b>VSMCs were cultured from the thoracic aorta of male Sprague-Dawley rats by the explant method. Subconfluent VSMCs were incubated with serum-free medium for 24 h to obtain quiescent non-dividing cells, and then treated with the indicated agents. The aliquots of VSMCs were labeled with testosterone-BSA-FITC (T-BSA-FITC) and analyzed by flow cytometry. Classical iARs in intact- and permeabilized-cells were detected with anti-iAR antibodies and FITC-labeled secondary antibodies by immunofluorescence, followed by flow cytometry analysis.</p><p><b>RESULTS</b>Incubation of VSMCs with T-BSA-FITC obviously increased their relative fluorescence intensity at 10 sec as compared with the untreated controls (P < 0.01), and so did it at 10 min in comparison with the treatment with BSA-FITC alone or together with free testosterone (P < 0.01). Pretreatment with iAR antagonist flutamide exhibited no significant influence on the relative fluorescence intensity of VSMCs (P = 0.318). Traditional iARs were not detectable on the surface of intact VSMCs, although permeabilized cells contained iARs.</p><p><b>CONCLUSION</b>VSMCs contain testosterone receptors in the plasma membrane, and these membrane receptors are not identical to classical iARs.</p>