
Originally Posted by
Merc.
Check this study out..... Very interesting ... Ginkgo biloba lowers prolactin ...
Horm Behav. 2007 Oct 10; [Epub ahead of print] LinksGinkgo biloba extract enhances male copulatory behavior and reduces serumprolactin levels in rats. Yeh KY, Pu HF, Kaphle K, Lin SF, Wu LS, Lin JH, Tsai YF.Department of Physiology, College of Medicine, National Taiwan University,Taipei, Taiwan, ROC.The aim of this study was to investigate the effects of Ginkgo bilobaextract (EGb 761) on male copulatory behavior in rats. EGb 761 (1 mg/ml)induced significant production of testosterone (T) in rat Leydig cells invitro. Its effects on sexual behavior were then tested in Long-Evans malerats after 7, 14, 21, or 28 days of oral gavage of vehicle (distilledwater) or EGb 761 at doses of 10, 50, or 100 mg/kg. Administration of 50mg/kg of EGb 761 for 28 days and of 100 mg/kg for 14 or 21 dayssignificantly increased intromission frequency compared to controls on thesame day. An increase in ejaculation frequency was seen after treatmentwith 50 mg/kg of EGb 761 for 14, 21, or 28 days when compared to eitherthe control group on the same day or the same group on day 0. A reductionin ejaculation latency was only seen after administration of 50 mg/kg ofEGb 761 for 14 days compared to the vehicle-treated group. After treatmentfor 28 days, no significant difference was seen in mount latency,intromission latency, serum T levels, reproductive organ weight, spermnumber, or levels of the metabolite of dopamine, 3,4-dihydroxyphenylaceticacid in the brain with any dose of EGb 761, but significantly reducedserum prolactin levels and increased dopamine levels in the medialpreoptic area and arcuate nucleus were seen at the dose of 50 mg/kg. Thesefindings show that EGb 761 (especially at the dose of 50 mg/kg) enhancesthe copulatory behavior of male rats and suggest that the dopaminergicsystem, which regulates prolactin secretion, may be involved in thefacilitatory effect of EGb 761.PMID: 18001735 [PubMed - as supplied by publisher]