There is mounting evidence that a family of guanosine triphosphate
binding proteins (G proteins) play an obligatory role in the transduction
of a vast array of extracellular, receptor-detected signals across cell
membranes to intracellular effectors. The author reviews the literature
dealing with G protein coupling to second messenger generation, the role of
G proteins in regulating both the convergence and divergence of
neurotransmitter action in the CNS, and the involvement of G proteins in a
variety of clinical conditions, with an emphasis on psychiatric conditions
and their treatments. G proteins from the basis of signal integration in
the CNS, endowing the neuron with a large degree of functional diversity.
Abnormalities in the function and/or expression of G proteins have been
implicated in a variety of pathophysiologic states, and a number of
currently available psychotropic drugs affect G proteins. The understanding
of the mechanisms by which G proteins modulate neuronal activity may be one
of the keys to understanding the functioning and the complexities of the
nervous system. Given their widespread, critical roles in the regulation of
neuronal function, it seems likely that G proteins are involved in the
pathophysiology of various major psychiatric illnesses. The development of
novel, site-specific drugs with primary G protein targets remains an
exciting prospect for the future.Abstract Teaser