Porcine vaginal mucosa as an in vitro permeability model for human vaginal mucosa

Abstract

The availability of human tissue for experimental purposes is often problematical and use is thus made of animal tissue as models of the human tissue. In this study, porcine vaginal mucosa was used as an in vitro permeability model for human vaginal mucosa using tritium-labelled permeants (17β-estradiol, r-arecoline, vasopressin, oxytocin and water). Fresh porcine and human vaginal tissues were frozen in liquid nitrogen and stored at −85 °C. In vitro permeability studies were performed using a flow-through diffusion apparatus (24 h, 20 °C, 1.5 ml/h). The mean steady state flux values for water, r-arecoline and vasopressin were approximately 4, 12 and 5% lower, while those for 17β-estradiol and oxytocin were approximately 17 and 53% higher, through porcine vaginal mucosa as compared to human vaginal mucosa, respectively. Using a F-test (comparing whole curves), statistically significant differences in the diffusion of 17β-estradiol, r-arecoline and oxytocin were indicated when comparing human and porcine vaginal mucosa. Generally, porcine vaginal mucosa seems a good in vitro permeability model for human vaginal mucosa. However, permeability of these two mucosa towards all permeants tested does not always correspond closely. These differences must always be considered when using porcine tissue as an in vitro permeability model for human vaginal mucosa.