336 / Biochemistry Testosterone

Gemzik, B., Halvorson, M.R. and Parkinson, A. (1990) Pronounced and differential effects of ionic strength and pH on testosterone oxidation by membrane-bound and purified forms of rat liver microsomal cytochrome P-450. Journal of Steroid Biochemistry, 35 (3-4), 429-440. 

Biochemistry provides the explanation for Porter s observations a decrease in the plasma concentration of testosterone could account for the inability to perform whilst die reduced extent of feedback inhibition on die pituitary would lead to an increased rate of secretion and hence an increase in die blood concentration of luteinising hormone, which has been claimed to increase the degree of sexual arousal in men. 

Of the many possible formulations tested all have proved to have unacceptable facets, generally including a very slow onset of action, uncertain reliability, and undesirable effects on biochemistry, body weight, or sexual function. However, some progress has been made with the combination of oral desogestrel and intramuscular testosterone. 

Hanioka N, Gonzalez FJ, Lindberg NA, et al. Site-directed mutagenesis of cytochrome P450s CYP2A1 and CYP2A2 influence of the distal helix on the kinetics of testosterone hydroxylation. Biochemistry 1992 31(13) 3364—3370. 

Ismail AA, Astley P, Cawood M, Short F, Wakelin K, Wheeler M. Testosterone assays guidelines for the provision of a cHnical biochemistry service. Ann Clin Biochem 1986 23 135-45. 

Diver, M.J. (2006) Analytical and physiological factors affecting the interpretation of serum testosterone concentration in men. Annals of Clinical Biochemistry, 43, 3-12. 

In medicine and biochemistry, the common or trivial names of compounds are used rather than the systematic nomenclature favored by chemists. Sometimes such names reflect functional groups, classes of compounds or the source from which the compound was first isolated. The compound testosterone provides an example. It was first isolated from monkey testis, the "ster" in its name denotes the steroid ring structure, and the "one" denotes a ketone group. 

Schanzer, W., Homing, S., Opfermann, G., and Donike, M. (1996) Gas chromatography/mass spectometry identification of long-term excreted metabolites of the anabolic steroid 4-chloro-l, 2-dehydro-17alpha-methyl-testosterone in humans. Journal of Steroid Biochemistry and Molecular Biology, SI, 363-376. 

Dehennin, L., and Matsumoto, A.M. (1993) Long-term administration of testosterone enanthate to normal men Alterations of the urinary profile of androgen metabolites potentially useful for detection of testosterone misuse in sport. Journal of Steroid Biochemistry and Molecular Biology, 44,179-189. 

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