Johnson, James D., Calvin J. H. Wong, Warren K. Yunker, and John P. Chang. Caffeine-stimulated GTH-II release involves Ca2 stores with novel properties. Am J Physiol Cell Physiol 282: C635–C645, 2002. First published November 7, 2001; 10.1152/ajpcell.00044.2001.—Modulation of Ca2 stores with 10 mM caffeine stimulates robust secretion of gonadotropin (GTH-II) from goldfish gonadotropes. Although...

During a 9-month period (corresponding to a sexual cycle), the adult male tench, Tinca tinca, was kept in fish farm ponds receiving heated water from a power plant. In 1974, the males were submitted to three different temperature regimes: group I: ambiant temperature; group II: ambiant temperature +3 degrees C; group III: ambiant temperature + 6 degrees C. The experiment was repeated in 1975, b...

This study was conducted to establish an in vitro maturation (IVM) system by selection of efficient porcine serum during porcine in vitro production. To investigate the efficient porcine serum (PS), different types of PS [newborn pig serum, prepubertal gilt serum (PGS), estrus sow serum, and pregnancy sow serum] were used to supplement IVM media with or without gonadotrophin (GTH) and developme...

Modulation of Ca(2+) stores with 10 mM caffeine stimulates robust secretion of gonadotropin (GTH-II) from goldfish gonadotropes. Although both endogenous forms of gonadotropin-releasing hormone (GnRH) utilize a common intracellular Ca(2+) store, sGnRH, but not cGnRH-II, uses an additional caffeine-sensitive mechanism. We examined caffeine signaling by using Ca(2+) imaging, electrophysiology, an...

To determine the effect of gonadal feedback on plasma GTH level, female rainbow trout were ovariectomized at three stages at the end of the reproductive cycle: at the end of vitellogenesis, during germinal vesicle migration and during the post-ovulatory period. A group of controls and one of castrates in each experiment were given an injection of physiological salt solution, and a third group o...