Metabolism of sex hormones in the aortic wall.

The metabolism of labeled sex hormones was examined in human, canine, and rat aortas. Isolated arterial tissue converted estrone to estradiol, estradiol to estrone, and estrone sulfate to estrone and estradiol. The arterial wall also appeared to metabolize testosterone to androstenedione and an unidentified, relatively nonpolar derivative. Both estrogens and testosterone appeared to enter the arterial wall rapidly. No competition in arterial uptake between the two hormones was apparent. No specific arterial binding of estradiol could be demonstrated. The concentration of estradiol-(3)H in the canine aorta exceeded that in the plasma 1-6 hr after estradiol-(3)H administration. The uptake and disappearance of estradiol-(3)H in the aorta generally resembled the patterns observed in body tissues other than the adrenal gland and uterus. The uptake of estradiol-(3)H was greatest in the adrenal gland while its retention was maximum in the uterus.