INFLUENCE OF STEROID SEXUAL HORMONES ON SKELETIZATION TIME OF WISTAR RATS

Abstract

The establishment of the postmortem interval is one of the most complicated and difficult tasks in forensic investigation because of many factors that affect this process (temperature, humidity, aerobic and anaerobic conditions, presence of microorganisms and soil conditions). Body intrinsic factors frequently not are related to de body decomposition. To investigate if the skeletonization process is under interference of sexual steroid hormones an experimental investigation with Wistar rats was done (30 male and 60 females divided in sub-groups at different hormonal phases). The animals were raised until they reach body weight between 350 and 450g, when were killed in a CO2 chamber and buried. Analysis of the environmental (temperature, humidity and rain) and corporal factors (body weight and body fat) showed that variation in these factors did not interfere on the skeletonization process. After the exhumation, only the male control group for testosterone showed complete skeletonization. The castrated males with no testosterone reposition and the castrated males with testosterone reposition showed minimum skeletonization. All female groups showed partial skeletonization. Analysis of the putrefaction residues from the groups with partial and minimum skeletonization showed the presence of the characteristic fatty acids of adipocere composition. Considering that both animal groups (males and females) were buried at the same place, under the same environmental and body conditions, during the same time interval, it is possible to conclude that sexual steroid hormones are responsible for the observed difference in body decomposition, being testosterone the main intervenient factor in this process. Besides, the experimental model also evidenced its potential use for future studies in the process of adipocere formation.