Effects of Saw Palmetto Extract on Urodynamic Function and Receptors in the Lower Urinary Tract

• FUJINO (OKI) Tomomi

  Department of Pharmacokinetics and Pharmacodynamics and Center of Excellence (COE) Program in the 21st Century, School of Pharmaceutical Sciences, University of Shizuoka

• SUZUKI Mayumi

  Department of Pharmacokinetics and Pharmacodynamics and Center of Excellence (COE) Program in the 21st Century, School of Pharmaceutical Sciences, University of Shizuoka

• YAMADA Shizuo

  Department of Pharmacokinetics and Pharmacodynamics and Center of Excellence (COE) Program in the 21st Century, School of Pharmaceutical Sciences, University of Shizuoka

Bibliographic Information

Other Title

• ノコギリヤシ果実抽出液の排尿機能及び下部尿路受容体に対する作用
• ノコギリヤシ カジツ チュウシュツエキ ノ ハイニョウ キノウ オヨビ カブ ニョウロ ジュヨウタイ ニ タイスル サヨウ

Abstract

Saw palmetto extract (SPE) is approved as a medicine for benign prostatic hyperplasia (BPH) in some European countries, and is also available as a healthy food product in Japan. Numerous pharmacological actions of SPE have been proposed, including 5α-reductase inhibition, and antiandrogenic, antiproliferative, antiinflammatory and antiedema effects. Furthermore, the clinical studies have shown that irritative and obstructive symptoms of BPH are alleviated by SPE. However, none of pharmacological effects of SPE has ever convincingly been shown to be therapeutically relevant in vivo. α₁-Adrenoceptor antagonists and muscarinic cholinoceptor antagonists are commonly used in the treatment of lower urinary tract symptoms in patients with BPH and overactive bladder (OAB). Thus, such improvement of voiding symptoms by SPE might be expected to arise from significant antagonism of α₁-adrenoceptors and muscarinic cholinoceptors in the lower urinary tract because SPE contains many constituents. The present study was undertaken to clarify pharmacological effects of SPE on urodynamic functions and autonomic receptors in the lower urinary tract. SPE may improve urodynamic symptoms in hyperactive bladders of acetic acid-infused rats by increasing bladder capacity and prolonging the micturition interval. It is notable that hyperactive rather than normal bladder was three-fold more sensitive to SPE. SPE exerted significant binding activities of α₁-adrenergic, muscarinic and 1,4-dihydropyridine (DHP) calcium channel antagonist receptors in the rat lower urinary tract. Furthermore, SPE also showed significant binding activities of prostatic α₁-adrenergic and bladder muscarinic receptor in humans. Repeated oral administration of SPE showed inhibitory tendency against significant increase of number of α₁-adrenergic receptor in testosterone-induced hypertrophied prostates of rats. Moreover, repeated oral administration of SPE did not influence activities of hepatic drug enzymes and blood biochemical parameters in rats. The present study may contribute significantly to the further understanding of pharmacological effects of SPE in the treatment of patients with BPH and OAB.<br>

Journal

• Japanese Journal of Complementary and Alternative Medicine

  Japanese Journal of Complementary and Alternative Medicine 4 (2), 41-50, 2007

  The Japanese Society for Complementary and Alternative Medicine

Keywords

• saw palmetto extract (SPE)
• urodynamic parameters
• prostatic α₁-adrenoceptors
• bladder muscarinic cholinoceptors

Details

• CRID: 1390282680197457920
• NII Article ID: 130000079381
• NII Book ID: AA12095429
• DOI: 10.1625/jcam.4.41
• ISSN: 13487930
• ISSN: 13487922
• ISSN: http://id.crossref.org/issn/02535076
• NDL BIB ID: 8881998
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I8881998
• Web Site: http://www.jstage.jst.go.jp/article/jcam/4/2/4_2_41/_pdf
• Web Site: https://search.jamas.or.jp/link/ui/2007290793
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed