Scurvy; a comparison between ultrastructural and biochemical changes observed in cultured fibroblasts and the collagen they synthesise

摘要: Earlier biochemical investigations of cultured 3T6 fibroblasts have shown that ascorbate deficiency has no effect on the synthesis collagen protein quantitatively but does produce inhibition critical post-translational hydroxylation essential for normal fibrogenesis and formation hydroxylysine-derived cross-links. This ultrastructural study same fibroblast system demonstrates not affect cell morphology, particularly synthetic or secretory apparatus, prevent deposition typical 640A degrees banded fibres; instead, finer, unbanded fibrils--presumably collagenous--are deposited extracellularly. confirms earlier findings as wll presenting a new finding--the inability ascorbate-deficient cells to lay down fibrils; possible mechanisms are considered in terms known lesions. The tissue culture also compared with those observed vivo scorbutic guinea-pig, where other workers reported evidence is inhibited. apparently paradoxical observations two systems considered; we conclude primary collagenous lesion which perhaps obscured by secondary effects--nevertheless approaches complementary.