The potential of collagenase as a new therapy for separation of human retained placenta: Hydrolytic potency on human, equine and bovine placentae

Abstract

The purpose of this study was to determine to what degree bacterial collagenase may digest human placentae compared to equine and bovine placentae. Placenta samples from human, equine and bovine were incubated with bacterial collagenase solution at various concentrations. The degree of hydrolysis and collagen breakdown was measured by the release of total proteins and hydroxyproline into the incubation media. Also, whole placentae were injected via umbilical cord arteries with collagenase solution (200 U/ml, 200 ml total volume in human and 1000 ml in equine) and hydrolysis determined chemically and subjectively. Human and equine placental collagens were the most sensitive to collagenase digestion. Overall mean collagenase activity determined by the release of hydroxyproline from human placenta was 1.6 times and in equine placenta three times greater than in bovine placenta, while the breakdown of non-collagenaus proteins remained negligible. When injected into whole placenta, the collagenase digested placentae evenly within 6–12 h. At 24 h, placentae were liquefied, although, umbilical blood vessels resisted collagenase digestion. Bacterial collagenase was highly effective in breaking down human placenta collagen. Intraplacental injections of collagenase via umbilical cord arteries may help to detach retained placenta in women as it does in mares and cows.