Hormones and postpartum cardiomyopathy.

Prolactin, a hormone fundamental for lactation, was recently shown to mediate postpartum cardiomyopathy, a life-threatening disease in late-term and lactating mothers. The detrimental effect of prolactin results from myocardial upregulation of cathepsin-D, which in turn cleaves prolactin to a 16 kDa fragment (vasoinhibin) with anti-angiogenic and pro-apoptotic properties that impair developing cardiac vasculature.