Serum prolactin levels are highest: (A) REM sleep, (B) 24 hrs after paurition, (C) 1 hr after running, (D) When Estrogens are high
Answer is A. Normaladult serum PRL levels are about10-25 mg/Linwomenand10-20 mg/L in men. PRL secretion is pulsatile, with the highest secretory peaks occurring during rapid eye movement sleep. Peak serum PRL levels (up to 30 mg/L) occur between 4:00 and 6:00 a.m. The circulating half-life of PRL is about 50 min.