1. Effects of various doses of intraperitoneal ouabain (1, 2 and 5 mg/
kg) on rat submandibular saliva were investigated in this study. 2. Po
tassium and calcium and their product (K+ x Ca2+) were found to be ele
vated in all groups. 3. Changes in salivary flow were not the major ca
use of the alterations in electrolytes. 4. Protein concentrations were
elevated in the doses of 1 and 2 mg/kg of the drug and somewhat reduc
ed ill the dose of 5 mg/kg of ouabain but still above the base line. 5
. The results show that there is an ouabain-induced close parallelism
between magnesium and total protein secretion from rat submandibular g
lands.