Question

please answer me in no more than 7 sentences. thanks

Please describe how the following changes can lead to muscle paralysis: 1. SNARE proteins are cleaved by a protease. 2. In the ligand-gated sodium channel on the muscle cell, the flanking charges around the first transmembrane domain are reversed.

Answer 1

1.The mechanism includes

action potential travels along presynaptic neuron$\Rightarrow$intracellular calcium influx$\Rightarrow$adherence od vesicles charged with acetyl choline to the presynaptic membrane$\Rightarrow$SNARE proteins$\Rightarrow$vesicle exocytosis$\Rightarrow$release of acetyl choline to the neuromuscular region$\Rightarrow$activation of post synapsis$\Rightarrow$opening of central ion channel$\Rightarrow$inward flux of Na+$\Rightarrow$muscle contraction.

when SNARE proteins are cleaved by protease it blocks the fusion of neuro transmitter containing vesicles to the plasma membrane and there by interuption of signal to muscles leads to muscle paralysis.

2.when the charges are reversed significant number of Na+ ions will move into the cell down their electrochemical gradient ,depolarizing the cell.