Semen, acid phosphatase

The adult male prostate contains abundant acid phosphatase which it secretes into the semen. The production of this enzyme is governed by the circulating levels of androgenic hormones. Castration or estrogen administration markedly reduces the prostatic urinary acid phosphatase of males. Other organs such as the liver, kidney, spleen, red cells and platelets also contain significant amounts of acid phosphatase. 

Acid phosphatase retains its activity for a long period and hence is useful in forensic science to detect semen but has now been superseded by DNA fingerprinting. The activity in blood was used in the diagnosis of prostatic cancer but was superseded by PSA (prostate specific antigen). 

Study of intermittent effluxes of acid phosphatase activity in the urine of mature human males 29) led to the discovery of the enzyme in semen and prostate by Kutscher and Wolberg (S). The enzyme is very active in human prostatic tissue and the caudal lobe of the rhesus monkey. Dog prostate contains much less enzyme than human tissue. Cat, guinea pig, rabbit, and rat prostates contain little (SO). Synthesis... 

The purpose of this project is to provide the theoretical and practical foundation for the improved analysis of semen in the context of rape investigations. The research has two primary objectives l) Improvement of procedures for the identification of semen and 2) Improvement of the ability to individualize semen. These objectives will be accomplished through an analysis of acid phosphatase and other proteins to determine whether the forms which are found in semen are unique to semen and whether they display genetic polymorphisms. A similar analysis will be done of the protein markers in the sperm cell membrane. 

Forensic biochemists perform blood typing and enzyme tests on body fluids in cases involving assault, and also in paternity cases. Even tiny samples of blood, saliva, or semen may be separated by electrophoresis and subjected to enzymatic analysis. In the case of rape, traces of semen found on clothing or on the person become important evidence the composition of semen varies from person to person. Some individuals excrete enzymes such as acid phosphatase and other proteins that are seldom found outside seminal fluid, and these chemical substances are characteristic of their semen samples. The presence of semen may be shown by the microscopic analysis for the presence of spermatozoa or by a positive test for prostate specific antigen. 

As long ago as 1935, Kutscher and Wolbergs (K12) observed that semen and the prostate are among the richest sources of acid phosphatase in the human body. In a more recent survey (Bll) the acid phosphatase activities of seminal plasma in various species, determined as milligrams of nitrophenol liberated by 100 ml seminal plasma from 0.006 M p-nitrophenyl phosphate, in 60 minutes at 37°C and pH 4.9 were human, 274,000 cock, 15,000 turkey, 4000 bull, 570 rabbit 85. Human seminal plasma is made up by the secretory fluids produced in the epididymides, vasa deferentia, ampullae, seminal vesicles, the prostate and the bulbourethral (Cowper s) and urethral (Littre s) glands (M4). The semen contains many particulate bodies. Best known, of course, are the spermatozoa, which are formed in the seminiferous... 

Semen is generally detected by identifying acid phosphatase or choline. The suspected stain is cut and incubated for 30 min at 37°C with two drops of a 0.1% aqueous solution of disodium phenyl-phosphate the phenol resulting from the enzyme-catalyzed hydrolysis can be detected with the Folin-Ciocalteu reagent. Phenol forms molybdenum blue on reaction with the molybdophosphate or tungstophosphate incorporated in this reagent. 

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