Studies on the Permeability of the Oral Mucosa I. Permeability of Inorganic Ions

¹ Department of Oral Physiology, Dental School, Osaka University, Kitaku, Osaka, Japan

The permeability of potassium, sodium, and calcium ions through the sublingual mucosa of a dog was studied. The results obtained are as follows.

1. Potassium and sodium ions were transported through the mucosa, and about 32 r/ml/20 minutes of K ions were detected when 10^-2 M KCl was applied. The rate of transport of Na ions was about 45 r/ml/20 minutes when 5 x 10^-3 M NaCl was applied.

The rates of transport of the ions were in proportion to the concentrations of the applied experimental solution in both cases. However, there are some differences in this transport process between the K ion and the Na ion flux across the membrane.

2. Transport of calcium ions across the membrane was not detected; however, Ca ions entered the membrane, where they were presumably bound with some unknown substance.