Cholinergic regulation of Na+-K+-ATPase activity in rat parotid gland: changes after castration
- 作者：Busch ; Lucila ; Sterin-Borda ; Leonor ; Borda ; Enri
- 关键词：Na+-K+-ATPase ; Parotid gland ; Carbachol
- 刊名：European Journal of Pharmacology
- 出版年：2004
- 期刊代码：24_00142999
- 类别：neu
- 出版时间：February 13, 2004
- 卷：486
- 期：1
- 页码：99-106
- 文件大小：416 K
摘要
In this study, we investigated the different signalling pathways involved in muscarinic acetylcholine M3 receptor-dependent modulation of Na+-K+-ATPase in parotid glands from normal and castrated rats. Carbachol inhibited the enzyme activity in parotid glands from control rats while it stimulated the enzyme activity in castrated rats. The inhibition of Ca2+ calmodulin by trifluoperazine abolished the inhibitory effect of carbachol in control rats, while the inhibition of protein kinase C by staurosporine stimulated Na+-K+-ATPase. In castrated rats, trifluoperazine inhibited the carbachol-stimulant effect while staurosporine had no effect. Results indicate that in control glands the activation of a phospholipid-Ca2+ calmodulin-dependent protein kinase C is responsible for the inhibitory effect of carbachol on Na+-K+-ATPase activity. In castrated rats, the activation of the enzyme by carbachol is regulated by its Ca2+ calmodulin-stimulating action, and not by activation of protein kinase C. The activation of the Na+-K+-ATPase observed in castrated rats resulted in a decrease in carbachol-induced net K+ efflux and thereby could decrease salivary fluid production.