Читать книгу Pathy's Principles and Practice of Geriatric Medicine - Группа авторов - Страница 370

CART is a peptide widely distributed in the brain, including the hypothalamus. In animals, central CART administration reduces feeding and blocks NPY‐induced feeding. Sohn et al. reported that arcuate nucleus CART mRNA levels were higher and NPY mRNA levels lower in healthy old than young male rats, whereas testosterone treatment of castrated, older rats significantly lowered CART mRNA levels and increased NPY mRNA levels. This suggests that in males, there is ageing‐related increased central activity of CART and reduced activity of NPY, both mediated by the normal age‐related decline in testosterone. This is an intriguing possibility, but the effects of ageing on CART in female animals have not been reported, nor have those in humans. The evidence that age‐related increases in central CART levels may cause the anorexia of ageing is currently derived from one study in male rodents.⁴³