EFFECTS OF BLOOD PH AND BLOOD LACTATE ON GROWTH-HORMONE, PROLACTIN, AND GONADOTROPIN-RELEASE AFTER ACUTE EXERCISE IN MALE-VOLUNTEERS

It has recently been found that prevention of the acidosis of anaerobi c exercise blocks beta-endorphin release. Because heavy exercise affec ts secretion of other anterior pituitary hormones, we studied the resu lts of alkali infusion and ingestion upon blood levers of four hormone s: luteinizing hormone (LH), follicle-stimulating hormone (FSH), growt h hormone(GH), and prolactin (PRL). Eight male subjects were studied a fter either 2 mE/kg placebo (NaCl) or alkali (NaHCO3) administered bef ore and during exercise to exhaustion. Blood samples were obtained bef ore exercise and then 15, 30, 60, 90, 120, and 180 min postexercise. G H and PRL but not FSH or LH increased significantly postexercise, with a peak at 60 min, and subsequently declined back to baseline by 180 m in. Base treatment reduced GH at baseline and postexercise (except at 60 min) and increased PRL significantly, particularly at 60 min. While the precise mechanisms on how acid/base changes affect hormone releas e remain to be defined, there are possible consequences on gonadal fun ction and substrate availability during exercise.