(684) Comparative Analysis of Seminal Vesicle and Vas Deferens Development in Normal and Anencephalic Human Fetuses

Introduction The seminal vesicle and vas deferens are organs of the male reproductive system that develop from the mesonephric duct in response to androgenic stimuli, potential stimulators of stromal differentiation and growth. Anencephaly is the most severe neural tube defect, a lethal malformation. Objective Our objective was to characterize and compare, using quantitative and qualitative methods, the muscular and fibrous components of the seminal vesicle and vas deferens in normal and anencephalic human fetuses during the second trimester of pregnancy. Methods Seventeen human fetuses without congenital anomalies (12 to 22 weeks post-conception) and ten anencephalic fetuses (11 to 16 weeks post-conception) were studied. The samples were fixed in 4% buffered formalin and processed for inclusion in paraffin. Five-micrometer-thick sections were made from each sample and stained using histochemical and immunohistochemical techniques for alpha-actin. The area density of the following components was analyzed: collagen fibers, smooth muscle fibers, and elastic system fibers. Histomorphometric analyses were performed on photomicrographs using ImageJ software. Statistical analysis was performed using GraphPad Prism 10 software (p < 0.05). Results In the anencephalic group, the seminal vesicle showed a significant decrease in collagen fibers (-78.97%; p = 0.0440) and in elastic system fibers (-41.99%; p = 0.0041); and the vas deferens showed a significant decrease in collagen fibers (-47.02%; p = 0.0451) and elastic system fibers (-38.86%; p = 0.0415). The linear regression analysis in the anecephalic group, between age and the components evaluated showed: vas deferens, significant and positive correlation only in collagen fibers (r2=0.8575; p=0.0080); in seminal vesicle there was no significant correlation. Conclusions During the second trimester of gestation, anencephaly caused significant changes in the development of the seminal vesicle and vas deferens, concerning fibrillar elements of the connective tissue. The smooth muscle cells appears to have been unaffected in the organs analyzed. Supported by grants from Rio de Janeiro Foundation for Research Support (FAPERJ) and National Council for Research Support (CNPq-Brazil) Disclosure No