In article <lbzpl140to.fsf at surf.usc.edu> Terrence Brannon,
brannon at surf.usc.edu writes:
>If ATP has its effects intracellularly and if synaptic receptors are
>not purinergic, then what is the physiological utility of such release?
Maybe it's an accident. There are ATPases in vesicular membranes, for
example there are vacuolar proton pumps that set up the gradients to
drive transport of neurotransmitter into the vesicle. I'm not sure what
side of the vesicular membrane the ATP binding/catalytic site is on, but
if it's inside then there would have to be ATP inside for these things to
work. The ATP would simply be released with neurotransmitter because it
would be more efficient to throw it away than to pump it back out against
its own gradient.
Matt