EFFECT OF TJ-96, AN ANTIALLERGIC HERBAL MEDICINE, ON TRACHEAL TRANSEPITHELIAL POTENTIAL DIFFERENCE IN-VIVO

We studied the effect of Saiboku-to (TJ-96), an anti-allergic herbal m edicine, on transepithelial potential difference of rabbit trachea and possible involvement of nitric oxide (NO) generation in vivo. Perfusi on of TJ-96 on the tracheal mucosal surface increased PD in a concentr ation-dependent manner, the maximal increase from the baseline level a nd the concentration of TJ-96 required to produce a half-maximal effec t (EC(50)) being 8.1 +/- 1.4 mV (mean +/- SE, P < 0.001) and 47 mu g/m l. This effect was abolished by pretreatment with the Na channel block er amiloride. N-G-nitro-L-arginine methylester (L-NAME) but not N-G-ni tro-D-arginine methylester (D-NAME) inhibited TJ-96-induced increase i n PD, and this inhibition was selectively reversed by L-arginine. Thes e results suggest that TJ-96 stimulates Na absorption by airway epithe lial cells probably through NO generation.