AUGUSTA, Ga. New studies indicate the three drugs used to treat male impotence also appear to work in females, albeit a little differently, and should give the scientific community pause to take a second look at their potential in the 40 percent of women who report sexual dysfunction, researchers say.
In one of the first studies of the effect of phosphodiesterase Type 5 inhibitors - Viagra, Levitra and Cialis - on the pudendal arteries that supply the penis, vagina and clitoris the blood needed to produce a satisfying sexual experience, Medical College of Georgia researchers showed the drugs relax the artery in male and female rats.
"It shows the drugs need to be investigated more for women and small alterations could make these compounds more effective for women living with these disorders," says Dr. Kyan J. Allahdadi, postdoctoral fellow in physiology at MCG. He's presenting the findings during the 122nd Annual Meeting of the American Physiological Society held in New Orleans April 18-22 as part of the Experimental Biology 2009 scientific conference.
Although there was talk years ago of a pink pill for women to parallel the blue Viagra for men, early clinical trials found essentially no response in women.
MCG researchers decided to look again, first giving a drug to constrict the internal pudendal arteries in male and female rats as they would be in a non-erect state then giving doses of each impotency drug to see the impact. The arteries from male rats displayed a relatively standard concentration-dependent relaxation the more drug they got, the more they relaxed - while in females arteries, there was an initial relaxation then an odd oscillation between relaxation and contraction with subsequent dosing.
While they don't fully understand the swing, the unique female response likely provides more evidence that sexual function is more complex in females, says Dr. R. Clinton Webb, chair of the MCG Department o
|Contact: Toni Baker|
Medical College of Georgia