Neuromuscular junction direct central nervous system

Toxic action is complex, involving both stimulation and blockade of autonomic ganglia and skeletal muscle neuromuscular junctions, as well as direct effects on the central nervous system. Paralysis and vascular collapse are prominent features of acute poisoning, but death is usually due to respiratory paralysis, which may ensue promptly after the first symptoms of poisoning. Nicotine is not an inhibitor of cholinesterase enzyme. 

There is some evidence which has been reviewed elsewhere that, at the neuromuscular junction and at synapses in autonomic ganglia, adrenaline and noradrenaline influence transmission without initiating the transmission process. At these sites, the catecholamines may act as modulators of transmission and the possibility that they may have a similar function in the central nervous system must be borne in mind. Direct evidence for such a central function is, however, lacking,... 

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