<Li> Agonists: GABA, Baclofen, gamma - Hydroxybutyrate, Phenibut etc . </Li> <Li> Positive Allosteric Modulators: CGP - 7930, Fendiline, BSPP, etc . </Li> <Li> Antagonists: 2 - OH - saclofen, Saclofen, SCH - 50911 </Li> <P> The cyclic - adenosine monophosphate (cAMP) - generating enzyme adenylate cyclase is the effector of both the G and G pathways . Ten different AC gene products in mammals, each with subtle differences in tissue distribution and / or function, all catalyze the conversion of cytosolic adenosine triphosphate (ATP) to cAMP, and all are directly stimulated by G - proteins of the G class . Interaction with Gα subunits of the G type, on the contrary, inhibits AC from generating cAMP . Thus, a GPCR coupled to G counteracts the actions of a GPCR coupled to G, and vice versa . The level of cytosolic cAMP may then determine the activity of various ion channels as well as members of the ser / thr - specific protein kinase A (PKA) family . As a result, cAMP is considered a second messenger and PKA a secondary effector . </P>

Where are ligand gated channels found on a neuron