title: The hormonal effects of Tribulus terrestris and its role in the management of male erectile dysfunction--an evaluation using primates, rabbit and rat.
abstract: Hormonal effects of Tribulus terrestris (TT) were evaluated in primates, rabbit and rat to identify its usefulness in the management of erectile dysfunction (ED). TT extract was administered intravenously, as a bolus dose of 7.5, 15 and 30 mg/kg, in primates for acute study. Rabbits and normal rats were treated with 2.5, 5 and 10mg/kg of TT extract orally for 8 weeks, for chronic study. In addition, castrated rats were treated either with testosterone cypionate (10mg/kg, subcutaneously; biweekly for 8 weeks) or TT orally (5mg/kg daily for 8 weeks). Blood samples were analyzed for testosterone (T), dihydrotestosterone (DHT) and dehydroepiandrosterone sulphate (DHEAS) levels using radioimmunoassay. In primates, the increases in T (52%), DHT (31%) and DHEAS (29%) at 7.5mg/kg were statistically significant. In rabbits, both T and DHT were increased compared to control, however, only the increases in DHT (by 30% and 32% at 5 and 10mg/kg) were statistically significant. In castrated rats, increases in T levels by 51% and 25% were observed with T and TT extract respectively that were statistically significant. TT increases some of the sex hormones, possibly due to the presence of protodioscin in the extract. TT may be useful in mild to moderate cases of ED.
authors: Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, National University of Singapore, 5 Lower Kent Ridge Road, 119074 Singapore. obgkg@nus.edu.sg <obgkg@nus.edu.sg>
authors: Kalamegam
authors: K
authors: Gauthaman
authors: Adaikan P
authors: AP
authors: Ganesan
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002369:Castration; D019314:Dehydroepiandrosterone Sulfate / Q000097:blood; D013196:Dihydrotestosterone / Q000097:blood; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004562:Electrocardiography / Q000187:drug effects; D007172:Erectile Dysfunction / Q000188:drug therapy*; D007279:Injections, Subcutaneous; D008253:Macaca mulatta; D008297:Male; D048530:Papio anubis; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D013045:Species Specificity; D013739:Testosterone / Q000031:analogs & derivatives / Q000097:blood / Q000627:therapeutic use; D032444:Tribulus / Q000737:chemistry*
chemical_list: D010936:Plant Extracts; D013196:Dihydrotestosterone; D013739:Testosterone; D019314:Dehydroepiandrosterone Sulfate; C016131:testosterone 17 beta-cypionate