Open AccessLactate and the effects of exercise on testosterone secretion: evidence for the involvement of a cAMP-mediated mechanism
Author(s) -
Shin-Shan Lu,
Chin-Pang Lau,
Yuh-Fan Tung,
ShengChieh Huang,
YenHao Chen,
Hsi-Chang Shih,
Shiow-Chwen Tsai,
Chunliang Lu,
Shyi-Wu Wang,
Jing-Jong Chen,
Eillen Jea Chien,
ChauHeng Chien,
Paulus S. Wang
Publication year - 1997
Publication title -
medicine and science in sports and exercise
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.703
H-Index - 224
eISSN - 1530-0315
pISSN - 0195-9131
DOI - 10.1097/00005768-199708000-00010
Subject(s) - endocrinology , medicine , testosterone (patch) , jugular vein , luteinizing hormone , human chorionic gonadotropin , gonadotropin , femoral vein , hormone , chemistry , biology
The effects of swimming and lactate on the release of testosterone were examined in male rats. During in vivo experiments, male rats were catheterized via the right jugular vein and blood was collected at 0, 10, 15, 30, and 60 min following the exercise, or they were catheterized via the right jugular vein and the left femoral vein and blood was collected at 0, 2, 5, 10, 15, 30, 60, and 120 min after a 10-min infusion at lactate (13 mg.kg-1.min-1). Trunk blood and blood from the testicular vein were also collected after 10 min of swimming or water immersion. In an in vitro experiment, testicular fragments were challenged with lactate (0.01-10 mM) and/or human chorionic gonadotropin (hCG; 0.5 IU.mL-1), and the mediobasal hypothalamus (MBH) was challenged with lactate (8 mM). The post-exercise levels of plasma lactate and testosterone at 10, 15, and 30 min were higher than resting levels. Plasma luteinizing hormone (LH) was increased following 30 min of swimming. Administration of lactate or hCG increased in a dose dependent manner testicular cyclic adenosine 3':5' monophosphate (cAMP) and testosterone release. Plasma testosterone increased after swimming and lactate infusion. Incubation of MBH with lactate increased the gonadotropin-releasing hormone (GnRH) level in the medium. These results suggest that the increased plasma testosterone levels in male rats during exercise is at least partially a result of a direct and LH-independent stimulatory effect of lactate on the secretion of testosterone by increasing testicular cAMP production. Swim-elevated plasma LH may be a result of a rise of GnRH caused by lactate.