Possible Roles of Superoxide in Hormonal and Neuromuscular Signal Transmission

Possible Roles of Superoxide in Hormonal and Neuromuscular Signal Transmission 

The search for the second messenger for mediation of insulin action has up to now been as unsuccessful as the quest for high-energy intermediates of oxidative phosphorylation. A not unreasonable possibility, therefore, is that the second messenger does not exist as a separate chemical entity and that insulin action is mediated by electronic processes involving macromolecular semiconduction. Support for this view comes from the finding that the most rapid observed action of insulin is a hyperpolarization of the muscle cell plasma 

MICHAEL N. BERHY. ANTHONY R. GRIVELL. and PATRICIA G. WALLACE 

It would also seem of value to explore further the molecular basis for the action of neurogenic amines capable of serving as transmitters at the neuromuscular or intersynaptic regions. It is known that these amines are catabolized (with superoxide production) within the outer mitochondrial membrane. The now well-recognized occurrence of flavin-linked superoxide-generating redox reactions within cellular plasma membranes raises the possibility that amine-induced signal transmission may be dependent on superoxide-linked transmitter metabolism after the transmitter binds to specific receptor sites. 

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