Abstract
Submicroscopic effects of insulin on the chondrogenesis and a micromelia were investigated with electron microscopic and histochemical methods, such as glycogen, acid phosphatase, acid mucopolysaccharide. The chondrogenic cells of the tibiotarsal anlage of 7 day chick embryos treated with 4 units of insulin on the 5th day of incubation had poorly differenciated cytoplasmic organelles. Glycogen granules conspicuously decreased in number than the control. After 5 days of the treatment the cells showed somewhat degenerative changes characterized by the degenerated cell organelles and the increase of acid phosphatase activity. Lead phosphate deposits were observed in the cisterna, vesicles of the Colgi areas and the lipid droplets. The glycogen granules totally disappeared from the cytoplasm. Seven days after the treatment the cells were decreased in number. The absence of Golgi vacuoles correlate with suppression of matrix formation. Matrix granules which showed ruthenium red positive reaction, remarkably decreased in number than the previous stages and only traces of them could be seen associated with fibrills.
