Expression of α1-Adrenergic Receptor Subtypes and Angiotensin II Type 1 Receptor in the Prostate of Spontaneously Hypertensive Rats

Background :To clarify the mechanisms of lower urinary tract symptoms (LUTS) associated with benign prostate hyperplasia (BPH), we investigated the expression of α1-adrenergic receptor (AR) subtypes and the angiotensin II type 1 receptor (AT1) within the prostate of spontaneously hypertensive rats (SHRs). Methods :Twelve male 25-week-old SHRs and Wistar Kyoto (WKY) rats were randomly separated into two groups (n =6 each). One group was given 20 ml 0.9% sodium chloride solution (saline) orally per kg-body weight daily for one week. The other group received no treatment. After 7 days of saline loading, systolic blood pressure (SBP) and prostate weight were measured. The prostates were immunohistochemically analyzed for α1-AR subtypes and AT1. Results :After 7 days, the SBP and prostate weight of saline-loaded SHRs tended to increase, but was not significantly different compared to the untreated rats.The expression ofα1-AR subtypes and AT1 within the prostates of saline-loaded SHRs was higher than in the untreated ones. In contrast, the expression in the saline-loaded WKY rat prostates did not increase compared to the untreated ones. Conclusion : Increased numbers of α1-AR subtypes and AT1 in saline-loaded SHR prostates might play important roles in the development of LUTS associated with BPH.Article信州医学雑誌. 58(3): 103-114 (2010)journal articl