Expression of LGR7 and LGR8 by neonatal porcine uterine tissues and transmission of milk-borne relaxin into the neonatal circulation by suckling

Abstract

Estrogen receptor-dependent organizational events between birth [postnatal day (PND) 0] and PND 14 affect development and function of porcine uterine tissues. Observations that uterotrophic effects of relaxin (RLX) in neonatal gilts were inhibited by the antiestrogen ICI 182,780 suggested that a RLX signaling system, capable of cross-talk with the estrogen receptor, evolves during a critical period for uterine programming (PND 0-14). Objectives were to determine 1) effects of age and estrogen exposure from birth on porcine uterine RLX/insulin-like 3 receptor (LGR7/LGR8) expression and 2) whether milk serves as a natural source of RLX in neonatal pigs. Uterine LGR7/LGR8 expression, detected b..