HUMAN ARTERIAL SMOOTH-MUSCLE CELL STRAINS DERIVED FROM PATIENTS WITH MOYAMOYA DISEASE - CHANGES IN BIOLOGICAL CHARACTERISTICS AND PROLIFERATIVE RESPONSE DURING CELLULAR AGING IN-VITRO

Moyamoya disease is a progressive cerebrovascular occlusive disease th at occurs frequently in children. The etiology is unknown. We examined changes in biological characteristics and responsiveness to serum mit ogens during the in vitro cellular aging of arterial smooth muscle cel l strains derived from patients with moyamoya disease (HMSMC) and comp ared them with those of cells from age-matched control patients (HCSMC ). HMSMC had a normal human diploid chromosome constitution. HMSMC and HCSMC had almost the same in vitro life span and the age-related patt erns of biological parameters were essentially the same. However, the doubling time at the early passages was significantly longer in moyamo ya SMC than control SMC, although there was no significant difference at the late passages. Furthermore, the poor responsiveness of moyamoya SMC to platelet-derived growth factor was retained throughout the lif e span in vitro. These results support the hypothesis that functional alterations in vascular cells are involved in the mechanism of develop ment of intimal thickening in moyamoya disease.