Lactate stimulates progesterone secretion via an increase in camp production in exercised female rats. Lu, Shin-Shan, Chin-Pang Lau, Yuh-Fan Tung, Seng-Wong Huang, Yen-Hao Chen, Hsi-Chang Shih, Shiow-Chwen Tsai, Chien-Chen Lu, Shyi-Wu Wang, Jing-Jong Chen, Eillen Jea Chien, Chau-Heng chien, and Paulus S. Wang. Departments of Physiology (SSL, CPL, YFT, SWH, YHC, HCS, SCT, CCL, EJC, CHC, PSW) and Physical Therapy (JJC), National Yang-Ming University, Taipei, and Department of Physiology (SSW),Chang Gung College of Medicine and Technology, Tao-Yuan, Taiwan, Republic of China
APStracts 3:0132E, 1996.
The effect of exercise on the production of ovarian progesterone (P) was examined in female rats. During in vivo experiments, diestrous rats were catheterized via right jugular vein (RJV) and blood samples were collected before and after 10, 15, 30, 60 min of the exercise. In addition, blood samples were collected from RJV before and 2, 5, 10, 15, 30, 60, and 120 min subsequent to 10 min infusion of lactate ( 13 mg/ml/min) through the left femoral vein. To explore if lactate modulate P secretion by acting directly on rat ovary or on anterior pituitary gland (AP), an in vitro experiment that mimicked in vivo condition was performed. The ovarian tissue was challenged with lactate (0.01-10 mM) or porcine follicle stimulating hormone (pFSH, 1 [acute]ugg/ml) and 3-isobutyl-methylxanthine (IBMX, 1 mM) for 60 min, and the AP was challenged with lactate ranging from 0.1-10 mM or 10 nM gonadotropin- releasing hormone (GnRH) for 30 min. The post -exercise levels of plasma glucose, lactate and P at 10, 15, 30 min were significantly higher than the corresponding basal levels. Plasma luteinizing hormone (LH) did not change following exercise. An elevation of plasma lactate and P was found at 15 and 30 min subsequent to 10 min infusion of lactate. Lactate ranging from 0.01 to 10 mM significantly increased ovarian cyclic adenosine 3',5' -monophosphate (cAMP) and P production in a dose-dependent manner. LH concentration in plasma was not change subsequent to exercise and lactate infusion. LH level in media samples was not altered following incubation of AP with lactate. These results suggest that the increase of plasma P level in rats during exercise is independent of LH secretion and at least in part due directly to a stimulatory effect of lactate on the production of ovarian cAMP. 

Received 11 April 1996; accepted in final form 25 June 1996.
APS Manuscript Number E183-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 25 July 1996