[Measurement of human seminal components and its medicolegal application]

Microdeterminations for low molecular compounds highly contained in human seminal plasma, i. e., dehydroepiandrosterone sulfate (DHEA-S), spermine (Sp) and citric acid (CA) have been established. Experimental studies were carried out on application of these methods to identification of semen from cadaveric vaginae more than a few days after death. DHEA-S was measured by radioimmunoassay using anti-DHEA-S-17-hydrazone conjugated bovine serum albumin rabbit antiserum. Sp and CA were determined spectrophotometrically with monoamine oxidase and with citrate lyase, oxalacetate decarboxylase and pyruvate oxidase, respectively. DHEA-S and its cross-reacting materials were contained little in saliva, moderately in semen and vaginal contents and largely in serum and urine. By the above method Sp was not detectable in other body fluids except semen. CA was contained not only largely in semen but also a little in other body fluids. DHEA-S and Sp in the seminal fluid allowed to stand at room temperature were relatively stable during a month, whereas CA became undetectable in 10 days, all of which being persistent in seminal stain during at least one month. From these results the colorimetry of Sp among the three methods above mentioned was found to be most reliable for detecting seminal fluid from vaginal contents of a putrefied cadaver.