Inhibition of airway smooth muscle tone by Chinese herbal medicines

Abstract

The aim of the present study was to elucidate whether Chinese traditional herbal drugs, Gorei-San (TJ-17) and Toki-Shakuyaku-San (TJ-23), affect airway smooth muscle tone and, if so, to determine what the mechanism of action is.Rabbit tracheal segments were isolated and the contractile responses to electrical field stimulation and acetylcholine were measured before and after the application of TJ-17 or TJ-23 under isometric conditions in vitro. Ouabain-sensitive rubidium-86 ( 86 Rb) uptake by tissues in response to each drug was also measured.Each herbal medicine attenuated the contractile responses to electrical field stimulation and acetylcholine in a concentration-dependent manner, the maximal inhibition of acetylcholine-induced contraction being 37.5 4.9% for TJ-17 and 42.4 5.3% for TJ-23 (p<0.05 for each). These effects were not altered by mechanical removal of the epithelium, indomethacin, the nitric oxide synthase inhibitor N G -nitro-L-arginine methyl ester, the cyclic adenosine monophosphate (cAMP)-dependent protein kinase inhibitor adenosine 3'5'-cyclic monophosphorothiioate (Rp-cAMPS), the cyclic guanosine monophosphate (cGMP)-dependent protein kinase inhibitor KT5823, or the calcium (Ca 2+ )-activated potassium (K + ) channel inhibitor charybdotoxin, but were greatly inhibited in the presence of the sodium (Na + )-K + adenosine triphosphatase (ATPase) inhibitor ouabain. Incubation of tissues with TJ-17 and TJ-23 dose dependently increased ouabain-sensitive 86 Rb uptake.The results of the study suggest that both Gorei-San and Toki-Shakuyaku-San reduce airway smooth muscle tone via a postjunctional mechanism probably through stimulation of the sodium pump and the subsequent hyperpolarization/repolarization of the cell membrane. These effects may contribute to the antiasthmatic properties of these herbal medicines.

Screening for Anti‐inflammatory and Bronchorelaxant Activities of 12 Commonly Used Chinese Herbal Medicines

“…The water extracts of GL and CS, which contains large molecules, may inhibit the Ca 2+ channels, resulting in attenuation of carbachol‐induced contraction. On the other hand, the CS ethanol extract, which contains small molecules, showed stronger inhibition in acetylcholine‐induced contraction, implying that the extract may exert its effects by acting directly on muscarinic receptors of smooth muscle cells (Tagaya et al , ; Yoshimura et al , ). The relaxant effects of these extracts will be further investigated to explore the underlying mechanisms.…”

Relaxant Action ofPlumula NelumbinisExtract on Mouse Airway Smooth Muscle

“…Some of traditional herbs have long been used in the treatment of asthma and COPD because they can effectively relax ASM contraction [ 9 – 11 ]. This inspired us to identify novel bronchodilators from the traditional herbs.…”

The Effect of Herbal Medicine Toki-shakuyaku-san on Blood Pressure in an Nω-Nitro-L-Arginine Methyl Ester-Induced Pre-eclampsia Rat Model During Pregnancy and the Postpartum Period

“…-dependent contraction of airway smooth muscle cells (31). Possible effects of TS on such pumps on the surface of vascular smooth muscle cells may deserve detailed examination.…”