biostudies-literatureFickling LJUniversity of Wisconsin-Madison (UW)HHS | NIH | National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)NIDDK NIH HHSWisconsin Alumni Research Foundation (WARF)NCRR NIH HHSHHS | NIH | National Institute of Neurological Disorders and Stroke (NINDS)NSF | EDU | Division of Graduate Education (DGE)NINDS NIH HHSUniversity of Pennsylvania (Penn)HHS | NIH | National Center for Research Resources (NCRR)NSF | MPS | Division of Chemistry (CHE)NIH HHS642-666https://www.ebi.ac.uk/biostudies/studies/S-EPMC12450063biostudies-literatureUnknown134(2)Studies of hormone influences on neural circuits and behavior have primarily focused on the manipulation of individual hormones. Here, we examine the influence of behavioral (feeding) state-specific hormonal environments on the gastric mill (chewing) circuit configured by the neuropeptide Gly¹-SIFamide (G-SIFamide) in the isolated <i>Cancer borealis</i> stomatogastric ganglion (STG). The G-SIFamide-activated gastric mill rhythm, which is similar to that driven by the G-SIFamidergic projection neuron modulatory commissural neuron 5 (MCN5), is distinguished from other gastric mill rhythms by the presence of rhythmic, prolonged inferior cardiac (IC) neuron bursts and associated interruptions of the pyloric rhythm. Applying 1 µM G-SIFamide in saline only occasionally activated the gJournal of neurophysiologyFeeding state-specific hormonal tuning of neural circuit modulation.PMC12450063NCRR-S10RR029531CHE-2108223NCRR-S10OD025084S10 OD028473S10 OD025084NCRR-S10OD028473R01-DK071801DGE-2137424R01 NS029436R01-NS029436R01 DK071801S10 RR029531Fickling LJIbarra AENusbaum MPWu WLi LCook APfalseFeeding state-specific hormonal tuning of neural circuit modulation.Studies of hormone influences on neural circuits and behavior have primarily focused on the manipulation of individual hormones. Here, we examine the influence of behavioral (feeding) state-specific hormonal environments on the gastric mill (chewing) circuit configured by the neuropeptide Gly¹-SIFamide (G-SIFamide) in the isolated <i>Cancer borealis</i> stomatogastric ganglion (STG). The G-SIFamide-activated gastric mill rhythm, which is similar to that driven by the G-SIFamidergic projection neuron modulatory commissural neuron 5 (MCN5), is distinguished from other gastric mill rhythms by the presence of rhythmic, prolonged inferior cardiac (IC) neuron bursts and associated interruptions of the pyloric rhythm. Applying 1 µM G-SIFamide in saline only occasionally activated the g2025-01-01T00:00:00Z2025 Aug2026-04-28T03:21:57.426Z2026-04-28T03:11:37.338ZS-EPMC124500634065859710.1152/jn.00164.2025