Aspetti istochimici della istolisi dei muscoli larvali nella metamorfosi di Musca domestica L. Attività e localizzazione della $\beta$-glucuronidasi

Russo-Caia, Salvatore ; Palatroni, Pietro

Atti della Accademia nazionale dei Lincei. Rendiconti della Classe di scienze fisiche, matematiche e naturali, Série 8, Tome 52 (1972) no. 2, pp. 233-238

Résumé

Hayashi simultaneous coupling method for the localization of lysosomal $\beta$-glucuronidase activity has been employed to study some histochemical aspects, mainly concerning the larval muscles histolysis, in metamorphosing Musca domestica. Contrary to the degeneration of midgut, which represents a typical autolytic process with the direct intervention of intracellular lysosomal enzymes, in the larval muscles histolysis B-glucuronidase is carried only by phagocytic cells. In no moment of pupal life is it in fact possible to detect an enzymatic activity in muscle fibers, whose fragmentation precedes phagocyte invasion. In these elements granular $\beta$-glucuronidase activity is present from the first stages and increases during the pupal life; in many cases haemocyte cytoplasm is at the end completely filled with large red masses. These findings are similar to those described in previous observations on the localization of acid glycerophosphatase and confirm - owing the particularly good specificity and accuracy of histochemical aspects - that in muscular histolysis there is not an activation of lysosomal hydrolases already present in muscle fibers.