Figure 8.

Signaling schematics. A, Optogenetic stimulation of POMC neurons primarily evokes release of glutamate and β-endorphin onto NPY/AgRP neurons. These findings suggest release is segregated such that GABA and α-MSH is released on to other neuronal subtypes. Acute and chronic activation of ERs increases the release probability of glutamate from POMC onto NPY/AgRP neurons. B, Activation of a Gq-coupled membrane-bound ER leads to the desensitization of GABA_B receptors. Decreased coupling between GABA_B and GIRK channels results in greater glutamate release from the terminal.