A HISTOCHEMICAL INVESTIGATION OF INTRAFUSAL FIBERS IN TORTOISE MUSCLE SPINDLES

Abstract
Histochemical investigations upon intrafusal muscle fibers of spindles in the extensor digitorum brevis 1 muscle of the tortoise have been carried out. The localization of phosphorylase, succinic dehydrogenase and adenosine activities together with the demonstration of lipids by the propylene glycol-Sudan method all failed to produce results which could be used to categorize the intrafusal fibers into more than one type. From these results and from previous histologic investigations it is suggested that the tortoise muscle spindle contains just one kind of intrafusal muscle fiber.