pancreatic peptide YY
a peptide released from the pancreas into the blood that inhibits excitatory transmission from the nucleus tractus solitarii to the dorsal motor nucleus of the vagus nerve, resulting in decreased vagal stimulation to the gastrointestinal tract. PYY also inhibits activity in the neurons of the arcuate nucleus that release agouti-related peptide (AgRP) and neuropeptide Y (NPY).
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Examples: glitazone, GI cocktail, etc.