Appetite and feeding is tightly regulated at the level of the hypothalamus by key neuronal populations, including the orexogenic (agouti-related peptide (AgRP)/neuropeptide Y (NPY)) and anorexogenic neuropeptides (pro-opiomelanocortin (POMC)).  POMC neurons in particular are sensitive to changes in inflammatory status and are the major perpetuators of inflammation-induced anorexia.  This anorexia partly arises from enhanced POMC expression by activation of pro-inflammatory transcription factor, NFkB.  Using a novel cell line, mHypoA-POMC/GFP-2  isolated from adult mouse hypothalamus (1), we demonstrate that TNFα-induced inflammation (100 ng/mL, 4 hrs) not only upregulates NFkB, but also the levels of inducible nitric oxide (NO^-) synthase (iNOS).  Induction of iNOS expression, subsequent NO^- production, and installation of nitrosative stress further enhances POMC mRNA levels. Exposure of POMC-GFP cells to the NO^- donor sodium nitroprusside (SNP; 100 μM, 4 hrs) is sufficient to enhance POMC mRNA levels without modulating NFkB expression, thus identifying nitrosative stress as an additional modulator of POMC expression in hypothalamic neurons. Furthermore, endogenous NO^- production by iNOS or by application of SNP greatly enhances insulin sensitivity of POMC-GFP neurons as shown from insulin induced phosphorylation of AKT and Foxo-1 and POMC mRNA levels.  Critically, heightened insulin sensitivity in response to TNFα or SNP is not due to changes in protein expression of the insulin receptor (IR), IR substrate-1 (IRS-1), phospho-tyrosine protein phosphatase 1B (PTP1B), or suppressor of cytokine signaling 3 (SOCS3).  In summary, TNF-induced inflammation and iNOS expression further upregulates POMC mRNA levels and insulin sensitivity in POMC-GFP hypothalamic neurons.  Future work will decipher the impact of NO^- on the transcriptional activation of the pomc gene, the stability of POMC mRNA, and the induction of post-translational modifications (S-nitrosylation) to key IR phosphatases, such as PTP1B. This work is generously supported by CIHR and CRC operating grants (DDB) and a CIHR post-doctoral fellowship (LW).