The effects of glycerol detubulation, of manganese ions, of dantrolene and of nitrate ions on the responses of isolated chronically denervated soleus muscles of the mouse to acetylcholine.
1 In the isolated chronically denervated soleus muscle of the mouse acetylcholine produced a biphasic contraction. 2 In muscles detubulated by glycerol treatment, the first phase of the acetylcholine contraction was almost abolished, but the second was only slightly reduced or was unaffected. 3 Manganese ions (10 mM) reduced the first phase of the acetylcholine response, but enhanced the second. 4 Dantrolene sodium (5.94 x 10(-5) M) reduced the first phase of the acetylcholine response, but not the second. 5 Nitrate ions (118 mM) augmented the first phase but not the second. 6 It was concluded that the first phase requires the excitation-contraction-coupling sequence: membrane depolarization-T-tubules-Ca2+ release from sarcoplasmic reticulum. In contrast, the second phase appears to occur independently of these processes.
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D003620:Dantrolene / Q000494:pharmacology*; D004347:Drug Interactions; D005990:Glycerol / Q000494:pharmacology*; D006827:Hydantoins / Q000494:pharmacology*; D066298:In Vitro Techniques; D008345:Manganese / Q000494:pharmacology*; D051379:Mice; D008870:Microtubules / Q000187:drug effects*; D009119:Muscle Contraction / Q000187:drug effects*; D009121:Muscle Denervation; D009132:Muscles / Q000187:drug effects / Q000648:ultrastructure; D009566:Nitrates / Q000494:pharmacology*; D012519:Sarcoplasmic Reticulum / Q000187:drug effects
D006827:Hydantoins; D009566:Nitrates; D008345:Manganese; D003620:Dantrolene; D000109:Acetylcholine; D005990:Glycerol