Modulatory effects of gonadorelin on GABA-induced depolarization and GABA-activated current in rat spinal ganglion neurons.
OBJECTIVE
To explore the modulatory effects of gonadorelin on GABA-induced depolarization and GABA-activated current in membrane of rat primary sensory neurons.


METHODS
Intracellular recordings and whole-cell patch clamp techniques were performed on neurons in rat spinal ganglia (SG) preparation and neurons freshly isolated from rat SG, respectively. Drugs were applied by superfusion and/or by bath application.


RESULTS
In the majority of neurons GABA (10 mumol.L-1 -1 mmol.L-1) induced a depolarization, which was blocked by bicucullin (100 mumol.L-1). Pretreatment with gonadorelin (50 mumol.L-1) decreased the GABA-induced depolarization by 79 +/- 22% (n = 29), while gonadorelin elicited no effect or slight depolarization alone. In 6 of 11 cells, GABA-activated currents were also inhibited by pretreatment with gonadorelin (50 mumol.L-1), while in 5 of 11 cells, there was no change or a slight potentiation.


CONCLUSIONS
Gonadorelin exerts an inhibitory effect on GABA-induced depolarization and GABA-activated current in the primary sensory neurons.
Zhou
X P
XP
Research Centre of Experimental Medicine, Tongji Medical University, Wuhan, China.
Wu
X P
XP
Guan
B C
BC
Li
Z W
ZW
D000818:Animals; D005260:Female; D018756:GABA Antagonists / Q000494:pharmacology; D018757:GABA Modulators / Q000494:pharmacology*; D005727:Ganglia, Spinal / Q000502:physiology*; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000502:physiology; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley
D018756:GABA Antagonists; D018757:GABA Modulators; D007987:Gonadotropin-Releasing Hormone