EOSINOPHILS INFILTRATION IN THE RAT SEMINAL-VESICLE ASSOCIATED WITH ESTRADIOL-17-BETA-RELATED STROMAL PROLIFERATION

We performed a histological quantitative analysis of collagen and smoo th muscle in seminal vesicle (SV) stroma after Estradiol-17 beta (E2) administration to the immature castrated rat. On day 14 after E2 admin istration, collagen and smooth muscle had increased approximately five and fifteen times, respectively, over the baseline of day 0. On day 2 8 (14 days after the cessation of E2 administration), smooth muscle de creased to the same level as that on day 7, but collagen did not decre ase during the 14 days after the cessation of E2 administration. As th e proliferation of stroma, the infiltration of eosinophils was seen in the perigrandular stroma that consisted of rich collagen. The number of infiltrated eosinophils increased exponentially in the period in wh ich collagen proliferated. But in the peripheral stroma which consists of rich smooth muscle, no eosinophil infiltration was seen. These res ults suggest that eosinophil infiltration into SV is related to E2 adm inistration and to stromal proliferation, especially to collagen proli feration in this condition.