The purpose of this investigation was to determine if prolonged incubation of pulmonary and coronary arteries with 0.1 micromolar dihydrotestosterone (DHT) affects the vascular response of the arteries to challenges with known constrictors and dilators, i.e. potassium chloride (KCl) and the nitric oxide donor NOC - 9. Porcine pulmonary and coronary arterial segments were obtained from DeVries Meats, Inc. and, then surgically dissected, mounted in isolated tissue baths, and incubated for two hours in DHT. The effect of the prolonged incubation was tested by measuring the change in arterial force when the vessels were constricted with KCl and relaxed with NOC - 9. The experimental group was compared with control arteries, which were not incubated with DHT. Preliminary results do not show consistent differences in the arterial responses, regardless of DHT incubation. The coronary arteries are more reactive than the pulmonary arteries to KCL and NOC-9. Further investigation of the vascular effects of prolonged arterial incubation with DHT will be required to come to a definitive conclusion regarding its effect on vascular function. It is hypothesized that guanosine 3', 5'-cyclic monophosphate (cGMP) is the second messenger responsible for acute, androgen-induced relaxations. To determine the concentration of cGMP in pulmonary and coronary arteries upon treatment with natural steroids, e.g. testosterone, DHT, androstenedione, and dehydroepiandrosterone, arterial segments were isolated and equilibrated in physiological salt solution for 30 minutes and then treated with the aforementioned steroids at varying concentrations. Following steroid treatment, samples were frozen in N2 (l) and ground to powder to be analyzed with a cGMP assay from Assay Designs, Inc. These studies are ongoing. This study was supported by a Student Summer Scholars grant at Grand Valley State University.
Faculty Mentor: Francis Sylvester
Page last modified July 14, 2009