Histochemistry of primate extraocular muscles and the changes of denervation.

The morphological and physiological classification of the fibres of the extraocular muscles has been the subject of some controversy, not to say confusion. It is well known that in mammals the oblique and rectus muscles consist of a peripheral layer of smaller fibres overlying a deeper zone with larger diameters (Kato, I938; Kern, I965). Many morphological and ultrastructural studies have described a dual type system in several species, including man, but later reports have suggested that this is an oversimplification. The application of histochemical methods to skeletal muscle has clarified the typing of the fibres and has enabled certain physiological properties to be inferred from their relative staining intensities. The purpose of the present study was to examine systematically control and denervated extraocular muscles in the baboon and control human material with a variety of histochemical and morphological techniques and to attempt to correlate the findings with those of other workers.