. 2015 Aug 1;37(4):81. doi: 10.1007/s11357-015-9821-x

Table 2.

Aging-related changes in peptides regulating appetite

↓ Sensitivity to opioids (β-endorphin, enkephalin, and dynorphin)^a

↓ Expression and number of receptors for neuropeptide Y (NPY)^a

↓ Expression and number of receptors for orexins^a

↓ Expression of agouti-related protein (AgRP)^a

↑/= Expression of cocaine- and amphetamine-regulated transcript (CART) (in men)

↑ Concentration of leptin (in men)

↓ Concentration of galanin (in women)

^aResults mostly from animal studies; human studies are inconclusive