[The metabolism of sulfur containing amino acids in the rat lens].
To determine the metabolism of sulfur containing amino acids in cultured rat lenses, the author studied the uptake and incorporation of radioactive amino acids (3H-leucine, 14C-glycine, 14C-cystine and 35S-methionine) into whole and fractions of the lens, and the effects of diethyl maleate (DEM), the inhibitions of glutathione (GSH) synthesis on them. The uptake and incorporation of radioactive amino acids with the exception of cystine into whole and fractions of the lens were decreased, especially in DEM-additive group. In DEM group, the uptake of cystine into whole lens was suppressed but that in control group was not. The incorporation of cystine into protein fraction (WIS, WS) were increased in DEM group. It was supposed that the decrease in the incorporation of glycine and the increase in that of cystine into protein fractions were related to the formation of high molecular weight proteins. It was also assumed that the decrease of the uptake of cystine into TCA soluble fraction was due to the inhibition of the synthesis of GSH.
Sakamoto
H
H
Second Department of Biochemistry, School of Medicine, Showa University, Shinagawa-ku, Japan.
Iijima
T
T
Sato
T
T
D000603:Amino Acids, Sulfur / Q000378:metabolism* / Q000493:pharmacokinetics; D000818:Animals; D005978:Glutathione / Q000037:antagonists & inhibitors; D066298:In Vitro Techniques; D007908:Lens, Crystalline / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008298:Maleates / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D000603:Amino Acids, Sulfur; D008298:Maleates; C014476:diethyl maleate; D005978:Glutathione