THE PYRAMIDAL TRACT. EFFECT OF MAXIMAL INJURY ON ACID PHOSPHATASE CONTENT IN NEURONS OF CATS

Abstract

Acid phosphatase was a normal constituent of the axis-cylinder. A histochemical technic, making possible the "staining" and localization of this enzyme, was applied to pyramidal tract axons following removal of their cells of origin. Unilateral decortications were performed on 16 cats, which were sacrificed at intervals between 1 and 365 days postoperative. Acid phosphatase disappeared from the axons between 2 and 3 days. The largest axis-cylinders; were first affected and the enzyme disappeared more rapidly from these fibers than those of smaller diam. Following the initial disappearance of phosphatase from the affected neurons, there was no reappearance, in association with glial elements, throughout the long process of secondary degeneration. This absence of the enzyme in chronic prepns. rendered it easily possible to trace degenerate tracts through brain or spinal cord. The results were discussed in terms of the possible role of the enzyme in carbohydrate and phospholipid metabolism of both axis-cylinder and myelin sheath.