老年性白内障晶状体蛋白质的改变

CHANGES IN HUMAN LENS PROTEINS IN SENILE CATARACT

The water-soluble, urea-soluble and intrinsic membrane proteins ( WSP, USP and MIP ) from human clear, cortical punctate opaque and senile cataract lenses were studied by gel filtration and SDS-PAGE . It was found that WSP decreased markedly in cataractous lenses. In cortical cataract, there was marked increase of HM + a-crystallin and decrease of P-and y-crystallins . In nuclear cataract, HN + ct- and 3-crystallins increased, but y-crystallin decreases. Besides, the loss of B-peak in cortical punctate opaque lenses was rather striking.The USP from cataractous lenses increased markedly. SDS-PAGE showed the USP from clear lenses contained aB chain as the main component. In cortical opaque and cortical cataract, the content of 27kDa polypeptide in p-crystallin increased markedly and 23kDa polypeptide appeared. In nuclear cataract, 23 and 27 kDa poly-peptides constituted the main components. The main components of MlP were 27 kDa and 23 kDa polypeptides ( MP27 and MP23 ) in both clear and cataractous lenses, but the relative amount of MP27 decreased slightly while that of MP23 increased in cataractous lenses.