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.
Referenze Bibliografiche
CROSSLEY A. C. S., An experimental analysis of the origins and physiology of haemocytes in the blue blow-fly Calliphora erythrocephala (Meig), «J. Exp. Zool.», 157, 375 (1964).
CROSSLEY A. C. S., Transformations in the abdominal muscles of the blue blowfly, Calliphora erythrocephala (Meig), during metamorphosis, «J. Embryol. Exp. Morphol.», 14, 89 (1965).
CROSSLEY A. C. S., The fine structure and mechanism of breakdown of larval intersegmental muscles in the blowfly Calliphora erythrocephala, «J. Ins. Physiol.», 14, 1389 (1968).
HAYASHI M., Distribution of $\beta$-glucuronidase activity in rat tissues employing the naphtol AS-BI glucuronide hexazonium pararosanilin method, «J. Histoch. Cytoch.», 12, 659 (1964).
HAYASHI M., NAKAJIMA Y. e FISHMAN W. H., The cytologic demonstration of $\beta$—glucuronidase employing naphtol AS-BI glucuronide and hexazonium pararosanilin; a preliminary report, «J. Histoch. Cytoch.», 12, 293 (1964).
HAYASHI M., SHIRAHAMA T. e COHEN A. S., Combined cytochemical and electron microscopic demonstration of $\beta$-glucuronidase activity in rat liver with the use of a simultaneous coupling azo dye technique, «J. Cell. Biol.», 36, 289 (1968).
HEGDEKAR B. M. e SMALLMAN B. N., Intracellular distribution of $\beta$-glucuronidase activity during metamorphosis of the housefly, Musca domestica L., «Canad. J. Zool.», 47, 45 (1969).
HERIN C., Étude de hydrolases acides lysosomiales des pupes du diptère Calliphora erythrocephala, «Arch. Intern. Physiol. Bioch.», 74, 315 (1966).
LOCKSHIN R. A., Lysosomes in insects, in «Lysosomes in Biology and Pathology» (Eds. J. T. Dingle & H. B. Fell), vol. 1, cap. 13; North-Holland, Amsterdam (1969 a).
LOCKSHIN R. A., Programmed cell death. Activation of lysis by a mechanism involving the synthesis of protein, «J. Ins. Physiol.», 15, 1505 (1969 b).
LOCKSHIN R. A. e WILLIAMS C. M., Programmed cell death. I. Cytology of degeneration in the intersegmental muscles of the pernyi silkmoth, «J. Ins. Physiol.», 11, 123 (1965 a).
LOCKSHIN R. A. e WILLIAMS C. M., Programmed cell death. V. Cytolytic enzymes in relation to the breakdown of the intersegmental muscles of silkmoths, «J. Ins. Physiol.», 11, 831 (1965 b).
PEREZ C., Recherches histologiques sur la métamorphose des Muscides; Calliphora erythrocephala Mg., «Arch. Zool. Exp. Gèn.», 4, 1 (1910).
RUSSO-CAIA S., Aspetti biochimici della metamorfosi degli Insetti. Osservazioni in Musca domestica L., «Ric. Scient.», 30, 1861 (1960).
RUSSO-CAIA S., Attività enzimatiche nel meso e metanefro dell'embrione di pollo, «Boll. Zool.», 31, 875 (1964).
RUSSO-CAIA S., Aspetti biochimici della metamorfosi degli Insetti. Attività solubile e sedimentabile della glicerofosfatasi acida nei tessuti larvali e pupali di Musca domestica, «Rend. Acc. Naz. Lincei», 39, 556 (1965).
RUSSO-CAIA S., Studi sul meso e metanefro delVembrione di pollo, «Acta Med. Rom.», 4, 469 (1966).
RUSSO-CAIA S., Osservazioni istochimiche sulla localizzazione della fosfatasi acida durante la metamorfosi di Musca domestica, «Rend. Acc. Naz. Lincei», 43, 129 (1967 a).
RUSSO-CAIA S., Osservazioni istochimiche sulla metamorfosi degli Insetti, «Boll. Zool.», 34, 168 (1967 b).
RUSSO-CAIA S. e CECERE F., Solubilizzazione di enzimi lisosomiali (proteinasi eribonucleasi acide) durante la regressione del mesonefro dell'embrione di pollo, «Ric. Scient.», 36, 1047 (1966).
RUSSO-CAIA S. e HASSAN G., Attività solubile e sedimentabile delle fosfatasi acide nello sviluppo e nella regressione del mesonefro dell'embrione di pollo, «Acta Embryol. Morphol. Expr», 8, 119 (1965 a).
RUSSO-CAIA S. e HASSAN G., Osservazioni istochimiche sulla glicerofosfatasi acida nel mesonefro in regressione dell'embrione di pollo, «Rend. Acc. Naz. Lincei», 39, 563 (1965 b).
RUSSO-CAIA S. e PALATRONI P., Osservazioni istochimiche sulla $\beta$-glucuronidasi nel mesonefro in regressione dell'embrione di pollo, «Rend. Acc. Naz. Lincei», in stampa (1971).
WHITTEN J. M., Haemocytes and the metamorphosing tissues in Sarcophaga bullata, Drosophila melanogaster, and other Cyclorrhaphous Diptera, «J. Ins. Physiol.», 10, 447 (1964).
WHITTEN J. M., Metamorphic changes in insects, in «Metamorphosis. A problem in Developmental Biology» (Eds. W. Etkin, L. I. Gilbert), cap. 2; North-Holland, Amsterdam (1968).
Con il contributo del Ministero per i Beni e le Attività Culturali