This study aimed to investigate the role of insulin-like growth factor-binding protein-3 (IGFBP-3) in erectUe dysfunction (ED) in two-kidney one-clip (2K-1C) hypertensive rats treated with the β-blocking agent propranolol. Adult male Wistar rats were randomly divided into three groups: a normal control group, a hypertensive control group and a propranolol treatment group (n=9). After 4 weeks of propranolol treatment, intracavemous pressure (ICP) responses to electrical stimulation of the cavernous nerves were evaluated. The expression of IGFBP-3 and insulin-like growth factor-1 (IGF-1) mRNA and protein in the rat cavernous tissue were detected by quantitative real-time PCR and Western blot, respectively. The concentration of cyclic guanosine monophosphate (cGMP) in the cavernous tissue was determined by enzyme-linked immunosorbent assay (ELISA). Cavernosal pressure in response to cavernous nerve stimulation was decreased 4 weeks after propranolol treatment (P〈0.01, compared to the hypertensive control group). IGFBP-3 mRNA and protein expression was increased in the propranolol treatment group compared to the hypertensive control group (P〈O.01), whereas IGF-1 expression was decreased in the propranolol treatment group compared to the hypertensive control group (P〈0.01). In addition, cavernous cGMP concentration was decreased in the prepranolol treatment group compared to the hypertensive control group (P〈0.01). Taken together, these results suggest that the upregulation of IGFBP-3 may play a role in the development of ED in hypertensive rats.
Zhang-Yan Zhou Zhong-Hua Yang Xing-Huan Wang Hong Cao Dong Chen Yong-Zhi Wang Hai-Hong Zhou Mou Peng Quan-Liang Liu Shao-Ping Wan
We investigated the effects of transient receptor potential M8(TRPM8)channel on the proliferation and motility of androgen-independent prostate cancer PC-3 cells.After being permanently transfected with an empty vector and cDNA encoding the TRPM8 protein,cells were analysed for cell cycle distribution and motility using flow cytometry and scratch assay.Immunocytochemistry and Ca^(2+)imaging analysis revealed the overexpression of functional TRPM8 channel on both endoplasmic reticulum and plasma membrane of PC-3-TRPM8 cells.Cell cycle distribution and scratch assay analysis revealed that TRPM8 induced cell cycle arrest at the G_(0)/G_(1)stage(P<0.05)and facilitated the cell apoptosis induced by starvation(P<0.05).Furthermore,TRPM8 inhibited the migration of PC-3-TRPM8 cells(P<0.01)through the inactivation of focal-adhesion kinase.It appears that TRPM8 was not essential for the survival of PC-3 cells;however,the overexpression of TRPM8 had negative effects on the proliferation and migration of PC-3 cells.Thus,TRPM8 and its agonists may serve as important targets for the treatment of prostate cancer.
Zhong-Hua YangXing-Huan WangHuai-Peng WangLi-Quan Hu