Fig. 7.

Activation of mTOR is necessary for amino acid-dependent inhibition of Agrp gene expression. GT1–7 cells were cultured in either 5 or 100% amino acids in the presence or absence of rapamycin (50 nm), generating four treatment groups. After 16 h of culture, cells were harvested, and RNA was extracted to assess Agrp gene expression via real-time PCR. Treatment with rapamycin had no effect on the already elevated Agrp mRNA levels in cells cultured in 5% amino acids but increased Agrp mRNA levels in cells cultured in 100% amino acids such that levels were significantly higher than those of cells cultured in 100% amino acids without rapamycin (*P = 0.01).