Effects of bromocriptine administration to pregnant rabbits upon fetal lung maturation

If endogenous prolactin secretion is important in normal development of fetal lung surfactant, the inhibition of its secretion should be associated with delayed maturation of fetal lung. We therefore studied the effect of bromoergocriptine administration to pregnant rabbits upon lecithin content of fetal lung washes. The does were treated since the 27th day of gestation with either Mesilate of 2-Bromo-alpha-ergocriptine (C32H40BrN5O5, CH3SO3H) (Bromocriptine) (Parlodel, Sandoz) (1 mg/kg/day) or solvent twice daily until delivery. The newborns were killed immediately by intraperitoneal administration of sodium pentobarbital and tracheostomized; then lung washes were performed. The extracted lipids were plated and run on heat-activated thin layers of silica gel H. Lecithin was eluted, and phosphorus determination was performed. The level of lecithin phosphorus in the lung washes of the fetuses whose mothers received Bromocriptine was X = 2.24 +/- 0.39 microgram/g dry lung weight, whereas that of fetuses of control does was X = 6.93 +/- 2.64 microgram/g dry lung weight (P less than 0.001). The mean body weight of the fetuses from treated mothers was 38.22 +/- 6.39 g whereas that of fetuses from control rabbits was 47.63 +/- 6.94 g (P less than 0.001). The mother's body weight gain from days 26 to 30 in Bromocriptine-treated rabbits was 156.11 +/- 99.4 g, whereas that of controls was 374.38 +/- 166.21 g (P less than 0.01).