Secretion of calcium by rat submandibular gland

Abstract

The mean concentration of calcium in rat submandibular gland saliva after maximal pilocarpine stimulation was initially 3.2 µEq/gm and gradually fell during the 1st hour to 0.93 µEq/gm. The final concentration was approximately 30% of the concentration of calcium in the serum ultrafiltrate whether the total serum calcium was normal or elevated threefold by the infusion of calcium chloride. At the end of the transient phase, the gland calcium concentration was from 28 to 57% less than the initial gland concentration depending upon the type of anesthesia used. The calcium loss from the gland correlated well with the excess calcium secreted in the saliva during the transient phase. After the initial transient phase was ended, the saliva calcium concentration bore an inverse relationship to the secretory rate and was directly proportional to the serum ultrafiltrate calcium concentration.