pubmed-article:2724694 | pubmed:abstractText | In guinea pig ileal muscle strips, trifluoperazine (TFP) inhibited the high K+-induced contraction with an IC50 of 1.9 microM and the Ca2+-induced contraction in skinned fiber with an IC50 of 44 microM. TFP decreased the high K+-induced increase in cytoplasmic Ca2+ level at the concentration 3 microM, which did not inhibit the contraction in skinned fiber. It is suggested that the inhibitory effect of TFP on the high K+-induced contraction is mainly due to the decrease in cytoplasmic Ca2+. | lld:pubmed |