"Chronic PC muscle (Kegel ) exercises not only train the prostate nervous reflexion for automatic contraction and fast ejaculation, but also stimulate the prostate itself to release oxytocin which in turn promotes the testosterone-DHT conversion locally and induces prostaglandin E-2 synthesis in the prostate, seminal vesicles and bulbourethral glands for precum flooding, semen leakage (emission), pains and of course, premature ejaculation."
http://www.actionlove.com/extra/pe.htm