Distribution and concentration of acid phosphatases in the nerve cord of the moth, Galleria mellonella, during metamorphosis

Localization and concentration of acid phosphatase in the nerve cord of metamorphosing Galleria mellonella were studied using sodium-α-naphtholphosphate (AS-BI) as substrate. Enzymatic activity is present in all stages of development in the cortex as well as in the neuropil and the connectives. Histochemical investigations indicated that much of the acid phosphatase activity is localized in the giant glial cells which adjoin the perilemma, and which branch extensively among the neuron perikarya. By 12 to 24 hr after pupal ecdysis this increased activity is striking. At 12 hr spectrophotometric tests of nerve cord extracts revealed a threefold increase in activity beyond that present in lightly spun-up larvae.