Open AccessStimulation of Na Absorption by the Antiasthmatic Kampo Drug Saiboku-To in Cultured Airway Epithelium.
Author(s) -
Jun Tamaoki,
Kiyoshi Takamatsu,
Atsushi Chiyotani,
Naotaka Sakai,
Takao Takizawa,
Kunihiko Konno
Publication year - 1992
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - English
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.58.47
Subject(s) - kampo , amiloride , ussing chamber , epithelium , stimulation , transepithelial potential difference , chemistry , absorption (acoustics) , respiratory epithelium , pharmacology , ion transporter , transcellular , intracellular , furosemide , in vitro , medicine , biochemistry , sodium , pathology , membrane , materials science , alternative medicine , organic chemistry , composite material
To study the effect of the Kampo drug Saiboku-to (TJ-96) on ion transport function of airway epithelial cells, we studied bioelectric properties of cultured tracheal epithelium from dogs under short-circuit conditions in vitro. Addition of TJ-96 (1 mg/ml) to the mucosal solution of the Ussing chamber increased the epithelial short-circuit current (SCC) from 6.5 +/- 0.7 to 11.4 +/- 1.6 microA/cm2 (P less than 0.001). This effect was dose-dependent, with the maximal increase from the baseline value and the concentration required to produce a half-maximal effect (EC50) being 70.5 +/- 12.6% (P less than 0.001) and 3 micrograms/ml, respectively; and there were corresponding increases in transepithelial potential difference and cell conductance. Submucosal addition of TJ-96 likewise increased SCC, although the magnitude of the response was smaller as compared with the response to the mucosal addition. The TJ-96-induced increase in SCC was not affected by diphenylamine-2-carboxylate or furosemide but abolished by amiloride. Intracellular cyclic AMP levels were dose-dependently increased by TJ-96. These results indicate that TJ-96 may selectively stimulate Na absorption across the tracheal epithelium, probably through intracellular accumulation of cyclic AMP.