Protein Synthesis in Rat Brain Microvessels Decreases with Aging

Abstract: The synthesis of protein by brain microvessels prepared from rats 4, 15, and 21 months of age was examined in organ culture. The rate of [³⁵S]methionine incorporation into trichloroacetic acid‐insoluble protein was lower in the vessels from older animals. These decreases were not dependent on the concentration of added methionine. Differences in protein synthesis could not be accounted for by specific peptidases in the incubation mixture. Polypeptide bands corresponding to actin and to the heavy and light chains of myosin were observed among the newly synthesized proteins following electrophoresis and autoradiography of the incubation mixture on polyacrylamide gels. The pattern of proteins synthesized, however, did not appear to vary significantly between young and old animals. Age‐related decreases in the synthesis of vascular proteins may contribute, in part, to some of the changes in the mechanical and functional properties of blood vessels during aging.