Highly active Na+, K+-ATPase in rat submaxillary gland bearing on salivary secretion

Abstract

A Na+, K+-ATPase was isolated from rat submaxillary glands by a combined deoxycholate-sodium iodide procedure. The activity of the relatively purified preparation was 300 [mu]moles Pi/mg protein/hr. which represents the most active mammalian Na+, K+-ATPase reported to date. The characteristics of the enzyme system are similar to those previously reported. Isoproterenol-induced hypertrophied glands revealed a Na+, K+-ATPase with markedly depressed activity. The data lend chemical support to the presence of an active electrolyte transport system in the ductal region of the rat submaxillary gland.