Influence of pH on Absorption of Nicotine from Urinary Bladder and Subcutaneous Tissues

Abstract

Summary

These experiments show that the hydrogen ion concentration plays an important rôCle in the absorption of nicotine from both the urinary bladder and the subcutaneous tissues. The toxicity of nicotine given by these routes is appreciably decreased when the pH of the solution is reduced within a certain range. At similar pH levels nicotine is absorbed from the urinary bladder and from the stomach at essentially similar rates. Absorption of nicotine from the subcutaneous tissues is greater than from the urinary bladder when the alkaloid is injected at similar pH values, but the impossibility of controlling the factors which influence absorption from the subcutaneous tissues precludes direct comparison as to the role of the pH alone.

A correlation is shown between the rate of absorption of nicotine from the urinary bladder and the calculated concentration of undis-sociated nicotine base in the solution injected.

The ligated urinary bladder provides a technic for the study of factors influencing absorption which is in some respects more satisfactory than the ligated stomach or intestinal loop, owing to the greater ease of controlling in the bladder certain variable factors such as the volume of fluid and the pH.