Key result
Verapamil and DIDS inhibit elevated muscular tone in pulmonary hypertensive rats via Cl- channel activation.
Elevated muscular tone in monocrotaline-induced pulmonary hypertension may be mediated by membrane depolarization via activation of DIDS-sensitive Cl- channels.
Answers are grounded in this paper and cite their sources.
Does not support clinical use; leaves open whether DIDS-sensitive Cl- channels mediate human pulmonary hypertension.
In monocrotaline-treated rat pulmonary artery from which endothelium was removed, greater spontaneous muscular tone was observed under resting conditions than in vehicle-treated artery. The aim of the present study was to show the possible contribution of Cl- channels in the mechanism of the elevated tone. Verapamil almost completely inhibited the elevated spontaneous muscular tone by decreasing [Ca2+]i. The elevated muscular tone was also inhibited by 4,4'-diisothiocyanato-stilbene-2,2'-disulfonic acid (DIDS), a Cl- channel inhibitor. After the inhibition of muscular tone by DIDS, verapamil did not induce further relaxation. Quantitative RT-PCR analysis indicated that the mRNA levels of ClC3 and Ca2+-activated Cl- channels did not change in the pulmonary hypertensive pulmonary artery from those of vehicle-treated rats. These results suggest that the elevated muscular tone observed in the monocrotaline-induced hypertensive pulmonary artery is due to membrane depolarization of smooth muscle cells and that this phenomenon might be mediated by the activation of DIDS-sensitive Cl- channels.
No takes yet. Share an insight, caveat, or question.
Nakazawa et al. (2001) studied Monocrotaline-induced pulmonary hypertension. Verapamil and DIDS vs. Vehicle was evaluated on Spontaneous muscular tone and Cl- channel mRNA levels. In monocrotaline-induced pulmonary hypertensive rats, elevated muscular tone was inhibited by verapamil and DIDS, suggesting mediation by DIDS-sensitive Cl- channel activation.
Synapse has enriched 10 related papers. Consider them for comparative context: