title: Contraction of detergent-treated smooth muscle.
abstract: After exposure of segments of rabbit taenia coli to the nonionic detergent Triton X-100, tension could be induced by increasing the [Ca2+] in the micromolar range. In the presence of a saturating [Ca2+], this preparation developed nearly 100% of the control tetanus tension recorded from the intact muscle prior to the detergent treatment. In addition, tension could be induced by increasing the [Mg2+], in the virtual absence of Ca2+. Mg2+ seems to inhibit the Ca2+-induced tension in a predominantly competitive manner.
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D004533:Egtazic Acid / Q000494:pharmacology; D005260:Female; D066298:In Vitro Techniques; D008274:Magnesium / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D011092:Polyethylene Glycols / Q000494:pharmacology*; D011188:Potassium / Q000494:pharmacology; D000644:Quaternary Ammonium Compounds / Q000494:pharmacology*; D011817:Rabbits
chemical_list: D000644:Quaternary Ammonium Compounds; D011092:Polyethylene Glycols; D004533:Egtazic Acid; D000255:Adenosine Triphosphate; D004492:Edetic Acid; D008274:Magnesium; D011188:Potassium; D002118:Calcium