Marchi reaction

Mar·chi re·ac·tion

(mahr'kē), failure of the myelin sheath of a nerve to blacken when submitted to the action of osmic acid.

Mar·chi reaction

(mahr'kē rē-ak'shŭn) Failure of the myelin sheath of a nerve to blacken when submitted to the action of osmic acid.

Marchi,

Vittorio, Italian physician, 1851-1908. Marchi fixative - used to demonstrate degenerating myelin.Marchi reaction - failure of the myelin sheath of a nerve to blacken when submitted to the action of osmic acid.Marchi stain - a method for demonstrating fat and degenerating nerve fibers.Marchi tract - a bundle of thick, heavily myelinated fibers originating in the deep layers of the superior colliculus. Synonym(s): tectospinal tract