Abstract: Objective To investigate the expression of 17 beta-hydroxysteroid dehydrogenase type 1 (17β-HSD1) in the kidney of
rats and explore the capacity of the kidney for synthesizing sex hormones. Methods The expressions of 17-HSD1 and sex
hormones were detected by Western blotting and radioimmunoassay in rat renal cells in primary cultured for 24 and 48 h in
the presence or absence of follicle-stimulating hormone (FSH) and luteinizing hormone (LH). Results After cell culture for 24
h, the primary rat renal cells expressed a low level of 17β-HSD1 (0.1843±0.076), which increased to 1.6651±0.044 (P<0.01) in
response to co-stimulation by FSH and LH. Low levels of estradiol, progesterone and testosterone were also detected in rat
renal cells (3.30±3.78, 62.60±12.33, and 22.12±3.36, respectively), and co-stimulation of FSH and LH significantly increased their
levels to 8.50 ± 2.64, 117.80 ± 9.79, and 45.04 ± 4.39, respectively (P<0.05). The levels of these hormones showed no significant
differences between cells cultured for 24 h and 48 h (P>0.05). Conclusion The rat renal cells express 17β-HSD1 and are capable
of stably secreting sex hormones in response to co-stimulation with FSH and LH, suggesting the capacity of the rat kidneys for
synthesizing sex hormones. These findings enrich the understanding of the endocrine function of the kidney.