When curare a south american indian arrow poison, is placed on a completely normal nerve skeletal mu

1.) cystic fibrosis is caused by a defect in a gated channel protein that normally transports chloride ions(Cl-). the channel protein is located in the cell membranes of epithelia lining the airways, sweat glands and pancreas. the opening of the channel is regulated through the binding of nucleotides to specific regions of the channel. what type of signaling is the channel protein involved in???
 

2.) when curare a south american indian arrow poison, is placed on a completely normal nerve skeletal muscle preparation, the muscle will not contract when the nerve is stimulated, even though acetylcholine is still being released from the nerve. what could explain how curare brings about this affect??
 
any suggestions would help thanks!