促黄体激素—促卵泡激素释放素对蟾蜍脊神经节细胞...

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.