relationship, therefore, increasing NPY availability could decrease alcohol intake. By creating a chemical antagonist for a Y2 receptor that would indirectly act as an agonist and stimulate Y1 receptors, alcohol consumption was successfully decreased in rats. Additionally, another similar study identified that NPY expression may be connected to behavioral regulation in relation to alcohol dependence. Administration of neuropeptide Y was found to reduce binge-drinking behavior. Although, it has been shown that NPY gene expression, mRNA or neuropeptide levels are not influenced by long-term alcohol consumption, but changes do occur during withdrawal from alcohol. These findings show that neuropeptide Y has varying effects on alcohol consumption. Two results suggest that NPY might protect against alcoholism: knock-out mice in which a type of NPY receptor has been removed show a higher voluntary intake of alcohol and a higher resistance to alcohol's sedating effects, compared to normal mice; the common fruit fly has a neuropeptide that is similar to NPY, known as neuropeptide F. The levels of neuropeptide F are lowered in sexually frustrated male flies, and this causes the flies to increase their voluntary intake of alcohol. Stress and anxiety Neuropeptide Y is considered to be an anxiolytic endogenous peptide and its levels can be modulated by stress. NPY has connections to the HPA axis and is believed to be necessary for stress modulation. It has been shown that higher levels of the Y1 and Y5 receptors in the amygdala result in reduced level of anxiety. Additionally, the Y1 receptor has been linked to anxiolytic effects in the forebrain while Y2 has been associated with the pons. Conversely, higher levels of NPY may be associated with resilience against and recovery from posttraumatic stress disorder and with dampening the fear response, allowing individuals to perform better under extreme stress. Studies of mice and monkeys show that repeated stress—and a high-fat, high-sugar diet—stimulate the release of neuropeptide Y, causing fat to build up in the abdomen. Researchers believe that by manipulating levels of NPY, they could eliminate fat from areas where it was not desired and accumulate at sites where it is needed. See also Anorexia nervosa Antianalgesia Incretin Neuropeptide Obesity References External links EMBL receptor database entry Neuropeptide Y peptides Neuropeptides