Organophosphorus pesticides are very effective, widely used, and pose a great risk to the environment and the health of various organisms, including humans. Dichlorvos (DDVP) is one of these pesticides and it has a mutagenic and carcinogenic potential for humans. Many pesticides, such as DDVP, act as endocrine disrupters and can alter endocrine homeostasis. These compounds act via androgen receptors (AR) or via estrogen receptors (ERs), promoting endocrine and reproductive changes, such as prostate cancer. Both androgens and estrogens are closely linked to the control of proliferation and cell death mechanisms that control normal prostate growth. Changes in the expression and activity of ARs and ERs are essential for understanding the process of carcinogenesis in the prostate.The present project aims to evaluate the expression of the AR, ERα and ERβ receptors in the ventral prostate of rats after exposure to the pesticide Dichlorvos, associated or not to chemical induction by MNU.A total of 40 rats of the Fischer 344 strain, at the age of 90 days, were used. Rats were randomly assigned to four experimental groups: Sham (G1), Sham + DDVP (G2), MNU (G3), MNU + DDVP (G4). For chemical induction, G3 and G4 were inoculated with MNU at 15 mg/kg, followed by daily subcutaneous injections of 2.5 mg/kg of testosterone cypionate for 20 days. Animals of the G2 and G4 groups, from 120 to 240 days old, received the basal diet supplemented with 10 mg/kg of DDVP. Western Blotting analysis of the ventral prostate was performed for AR (fig. 1), ERα (fig. 2) and ERβ (fig. 3) with β‐actin (fig. 4) loading control.In the densitometric analysis, it was verified that the expression of AR is higher in the G2 group than in the G1. When comparing the G3 group to the G1 group, it is noted that the expression of AR is higher in the G3 group. Thus, it is possible to infer that the expression of AR increases, both after exposure to DDVP and after chemical induction by MNU (fig. 5).In the densitometric analysis, it was also verified that ERα expression is higher in the G2 group than in the G1 group. When comparing the G3 group to the G1 group, it is noted that the ERα expression is higher in the G3 group. It is also observed that the ERα expression is higher in the G4 group than in the G2 group. The G4 group, on the other hand, presents ERα expression equal to that of G3. Thus, it is possible to infer that ERα expression increases, both after exposure to DDVP and after chemical induction by MNU (fig. 6).It has also been shown that ERβ expression is lower in the G2 group than in the G1 group. When comparing the G3 group to the G1 group, it is noted that the ERβ expression is lower in the G3 group. It is also observed that the ERβ expression is lower in the G4 group than in the G2 group. The G4 group, on the other hand, has lower ERβ expression than G3. Thus, it is possible to infer that ERβ expression decreases, both after exposure to DDVP and after chemical induction by MNU (fig. 7).Thus, we can conclude that the exposure to the pesticide DDVP alters the expression of hormone receptors in the ventral prostate of rats and can act as an endocrine disruptor.Support or Funding InformationFapesp 2014/07329‐0This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.