A new method for drug transport studies on pig nasal mucosa using a horizontal Ussing chamber

The horizontal Ussing chamber method described here allows performance of transport studies on pig nasal respiratory mucosa under conditions simulating reality in that it mimics the air-mucosa interface. The transport of testosterone and mannitol through pig nasal mucosa in the horizontal Ussing chamber was investigated using both liquid and air mucosal interfaces. There were no significant differences in either the bioelectrical parameters (transmucosal electrical resistance, R, potential difference, PD, and short circuit current, I(sc)) or the apparent permeability (P(app)) of the mucosa to testosterone or mannitol between the liquid and air interface experiments. The histological study showed that the epithelial cell layer tolerates exposure to the air interface well. The P(app) equation was developed to correct for substance binding to the wall of the receiver chamber. The mean values +/- SD of R, PD, and I(sc) for the mucosae in the study were 75.0 +/- 28.0 Omegacm(2), (-4.53) +/- 3.46 mV and 58.6 +/- 28.8 microA/cm(2), respectively. The corrected P(app) for testosterone with and without the mucosal air interface were 9.82. 10(-6) +/- 11.41. 10(-6) cm/s and 32.24. 10(-6) +/- 31.12. 10(-6) cm/s, respectively. The P(app) values for mannitol with and without the air interface were 2.26. 10(-6) +/- 1.42. 10(-6) cm/s and 3.12. 10(-6) +/- 1.72. 10(-6) cm/s, respectively.