Effect of dietary protein quality and feeding level on milk secretion and mammary protein synthesis in the rat

Journal Article · Mon Apr 01 04:00:00 EST 1985 · J. Pediatr. Gastroenterol. Nutr.; (United States)

DOI:https://doi.org/10.1097/00005176-198504000-00020· OSTI ID:5125351

Sampson, D A; Jansen, G R

Protein synthesis was studied in mammary tissue of rats fed diets deficient in protein quality and/or restricted in food intake throughout gestation and lactation. Diets containing 25% wheat gluten (WG), wheat gluten plus lysine and threonine (WGLT), or casein (C) were pair-fed from conception until day 15 of lactation at 100% or 85% of WG ad libitum consumption (PF100 and PF85, respectively). A seventh group was fed C ad libitum. Rates of protein synthesis were measured in vivo at day 15 of lactation from incorporation of (3-/sup 3/H)phenylalanine. At both PF100 and PF85, fractional and absolute rates of mammary gland protein synthesis were two- to three-fold higher in rats fed C than in those fed WG. Pup weights showed similar treatment effects. Both mammary protein synthesis rates and pup weights were significantly higher in rats fed C at PF85 than rats fed WG ad libitum. Food restriction from PF100 to PF85 depressed pup weights and mammary protein synthesis rates in rats fed WGLT, but had no effect in rats fed WG. These results demonstrate that when food intake is restricted, improvement of protein quality of the maternal diet increases milk output in the rat in association with increased rates of mammary protein synthesis.

• Research Organization: Colorado State Univ., Fort Collins
• OSTI ID: 5125351
• Journal Information: J. Pediatr. Gastroenterol. Nutr.; (United States), Journal Name: J. Pediatr. Gastroenterol. Nutr.; (United States) Vol. 2; ISSN JPGND
• Country of Publication: United States
• Language: English

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
ANIMALS
BIOLOGICAL EFFECTS
BIOLOGICAL MATERIALS
BIOSYNTHESIS
BODY
BODY FLUIDS
CARBOXYLIC ACIDS
DIET
DNA
FOOD
GLANDS
LABELLED COMPOUNDS
LACTATION
MAMMALS
MAMMARY GLANDS
MATERIALS
MILK
NUCLEIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
PHENYLALANINE
PREGNANCY
PROTEINS
RATS
RNA
RODENTS
SYNTHESIS
TRITIUM COMPOUNDS
VERTEBRATES