Fig. 3.

Lubiprostone induces a chloride SCC more efficiently if applied to the apical surface than to the basolateral surface of sheep tracheas. An example of 1 matched pair is given in A. Six matched pairs of ventral epithelia were exposed to 200 nM lubiprostone on either the apical or basolateral side. Amiloride was added apically and bumetanide basolaterally. B shows the means ± SE for the peak changes in SCC (ΔμA cm⁻²), the time taken to reach the peak value (seconds), and the time for the responses to begin (seconds). The repeatability and reversibility of lubiprostone action was investigated as shown in C. Here are shown results for repeated application of 200 nM lubiprostone (apically) at 0, 1, and 3 h with extensive washing between each addition. Data for both dorsal and ventral epithelia of sheep are shown. NS, not significant.