[Effect of LH-FSH releasing hormone on the sensitivity of cholinergic and adrenergic receptors in toad spinal ganglion neurons].
Intracellular recordings were performed on 81 neurons from 53 isolated toad spinal ganglia (SG). The effects of LH-FSH releasing hormone on the sensitivities of muscarinic receptors and alpha-adrenoceptors located on the soma of SG neurons were observed. Perfusing SG with atropine 10 mumol.L-1 in Ringer's solution depressed the amplitude of depolarization response induced by acetylcholine (ACh, 10-100 mumol.L-1). The depolarization and hyperpolarization induced by norepinephrine (NE, 10-100 mumol.L-1) were blocked by alpha 1-adrenoceptor antagonist prazosin and alpha 2-adrenoceptor antagonist yohimbine respectively. These results indicated that ACh-induced depolarization was mediated by muscarinic receptors while NE-induced depolarization and hyperpolarization were mediated by alpha 1- and alpha 2-adrenoceptors respectively. On the other hand, perfusing SG with LH-FSH releasing hormone 10 mumol.L-1 in Ringer's solution increased the depolarization response caused by ACh or NE, but attenuated NE-caused hyperpolarization response. The above results suggest that LH-FSH releasing hormone may modulate the sensitivities of muscarinic receptors and alpha-adrenoceptors on the soma membrane of toad SG neurons.
Wang
A J
AJ
Research Center of Experimental Medicine, Tongji Medical University, Wuhan, China.
Hu
M X
MX
Li
Z W
ZW
D000818:Animals; D002023:Bufo bufo; D005260:Female; D005727:Ganglia, Spinal / Q000502:physiology*; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009474:Neurons / Q000502:physiology; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects*; D011976:Receptors, Muscarinic / Q000187:drug effects*
D011942:Receptors, Adrenergic, alpha; D011976:Receptors, Muscarinic; D007987:Gonadotropin-Releasing Hormone