Cats
granules vary in size, with some being massively enlarged. Electron microscopic examination
of retinal pigmented epithelium of kittens with Chediak-Higashi syndrome disclosed a
number of abnormalities of premelanosomes and melanosomes. Few premelanosomes were
present. Most of the melanin granules were giant sized, but their structures varied. Some of
the giant granules were composed of several premelanosomes and melanosomes in different
stages of maturation. Others contained randomly oriented melanofilaments between
melanosomes. There were also complex giant granules consisting of both melanosomal and
lysosomal components. Inappropriate fusion of cytoplasmic granules appears to be the most
likely mechanism for formation of the giant granules. Fusion of premelanosomes with
lysosomes and resultant destruction of the premelanosomes probably is a major cause of the
ocular hypopigmentation of Chediak-Higashi syndrome."
Hargis AM, Prieur DJ
annaabi.ee 
