ABSTRACT
This chapter explores how dietary protein and carbohydrate affect hormonal secretion and genes that encode several inducible enzymes. Although amino acids serve a common purpose during protein synthesis, each amino acid has unique properties and functions in interorgan metabolism, some of which may influence gene expression. The amount of protein relative to DNA increases, suggesting that protein or amino acids promote both hypertrophy and hyperplasia; hyperplasia predominates in young rats and hypertrophy predominates in older ones. In addition to their effects on organ growth, amino acids rapidly increase the rate of renal blood flow and glomerular filtration rate. Tissues that contain receptors for the peptide hormones may respond to diet-induced secretion of the gut peptides. Nutrient status strongly modifies hormonal secretion from the pituitary gland, and this effect is thought to be mediated by altered synthesis and secretion of neurotransmitters and releasing factors from specific areas in the hypothalamus.
