Testosterone blood production rate

Furthermore Tait and co-workers [322] pointed out the marked difference in the urinary and blood production rates of testosterone obtained in women after injection of radioactive testosterone. He concluded that steroids produced from dehydroepiandrosterone contribute little to the blood production rate of androstenedione and testosterone in normal subjects [403]. According to Tait [324], all the blood production rate of androstenedione in the female and testosterone in the male is due to the same secreted steroid, while the blood production rate of testosterone in the female and androstenedione in the male is due about one-half to the same secreted steroid and one-half to converted precursor. The normal male secretes a ratio of testosterone to androstenedione of about 10 1 and the normal female secretes a ratio of androstenedione to testosterone of about 25 1. 

I) Consider three structurally similar Cis steroids —testosterone, an-drostenedione, and dehydroepiandrosterone. Each of these compounds is secreted into the blood stream by glands, and after provoking its biochemical effect, is metabolized and excreted. If the only source of the plasma pool were provided by the glandular secretion of the hormone, then the secretion rate would be used to calculate the plasma concentration. However, the picture in the case of the three Ci steroids is complicated by the fact that the three compounds are peripherally interconvertible. Since both glandular secretion and peripheral conversion of precursors contribute to the plasma pool, the production rate is used to... 

Tait, J. F., and Horton, R., The in vivo estimation of blood production and interconversion rates of anderstenedione and testosterone and the calculation of their secretion rates. In Steroid Dynamics (G. Pincus, J. F. Tait, and T. Nakao, eds.), pp. 393-425. Academic Press, New York, 1966. 

Studies undertaken to study the role of other endocrine activity in these changes showed that injections of norepinephrine and ACTH decreased the rate of production of testosterone and lowered the plasma level. Injections of cortisone alone had no effect on blood testosterone levels (C2). 

H6. Horton, R., and Tait, J. F., Androstenedione production and interconversion rates measured in peripheral blood and studies on the possible site of its conversion to testosterone. J. Clin. Invest. 45, 301-313 (1966). 

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