ATP activates junctional and extrajunctional acetylcholine receptor channels in isolated adult rat muscle fibres.
Single-channel recordings in the cell-attached configuration were made on freshly dissociated and cultured rat muscle fibers. We demonstrate that ATP (50-100 microM) elicits single channel currents in freshly isolated fibres. These ATP-activated channels have a slope conductance similar to that determined for ACh-activated channels but exhibit a shorter open time. We also show that ATP activates extrajunctional AChR-channels in the membrane of long-term cultured muscle fibres. Here the ATP activated channel has a slope conductance and open time characteristics similar to those of the ACh-activated channel.
Mozrzymas
J W
JW
Institute of Physiology, University of Trieste, Italy.
Ruzzier
F
F
D000109:Acetylcholine / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects*; D009132:Muscles / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D009469:Neuromuscular Junction / Q000187:drug effects*; D051381:Rats; D011950:Receptors, Cholinergic / Q000187:drug effects*
D007473:Ion Channels; D011950:Receptors, Cholinergic; D000255:Adenosine Triphosphate; D000109:Acetylcholine