Intracellular mechanisms involved in copper-gonadotropin-releasing hormone (Cu-GnRH) complex-induced cAMP/PKA signaling in female rat anterior pituitary cells in vitro.

Intracellular mechanisms involved in copper-gonadotropin-releasing hormone (Cu-GnRH) complex-induced cAMP/PKA signaling in female rat anterior pituitary cells in vitro.
Brain Res Bull. 2015 Nov 6;
Authors: Gajewska A, Zielinska-Gorska M, Wolinska-Witort E, Siawrys G, Baran M, Kotarba G, Biernacka K
Abstract
The copper-gonadotropin-releasing hormone molecule (Cu-GnRH) is a GnRH analog, which preserves its amino acid sequence, but which contains a Cu(2+) ion stably bound to the nitrogen atoms including that of the imidazole ring of Histidine(2). A previous report indicated that Cu-GnRH was able to activate cAMP/PKA signaling in anterior pituitary cells in vitro, but raised the question of which intracellular mechanism(s) mediated the Cu-GnRH-induced cAMP synthesis in gonadotropes. To investigate this mechanism, in the present study, female rat anterior pituitary cells in vitro were pretreated with 0.1μM antide, a GnRH antagonist; 0.1μM cetrorelix, a GnRH receptor antagonist; 0.1μM PACAP6-38, a PAC-1 receptor antagonist; 2μM GF109203X, a protein kinase C inhibitor; 50mM PMA, a protein kinase C activator; the protein kinase A inhibitors H89 (30μM) and KT5720 (60nM); factors affecting intracellular calcium activity: 2.5mM EGTA; 2μM thapsigargin; 5μM A23187, a Ca(2+) ionophore; or 10μg/ml cycloheximide, a protein synthesis inhibitor. After one of the above pretreatments, cells were incubated in the presence of 0.1μM Cu-GnRH for 0....

Source: Brain Research Bulletin - November 6, 2015 Category: Neurology Authors: Gajewska A, Zielinska-Gorska M, Wolinska-Witort E, Siawrys G, Baran M, Kotarba G, Biernacka K Tags: Brain Res Bull Source Type: research