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M S BURSTONE

Publications and source records attributed to M S BURSTONE.

At least 19 recordsLinked to original sources
PubMed1964

LOCALIZATION OF ESTERASE AND ACID PHOSPHATASE IN GRANULES AND COLLOID DROPLETS IN RAT THYROID EPITHELIUM.

Droplets which stain like colloid occur in the cytoplasm of the thyroid follicular epithelium of the rat following stimulation of the gland by thyroid-stimulating hormone (TSH). The occurrence of droplets was remarkably reduced when the lumen became depleted of colloid. Acid phosphatase and esterase were localized in the thyroid droplets and, in addition, in granules largely around the nucleus. Stimulation by TSH resulted in an increase in the number of droplets containing enzyme. Twenty-four hours after hypophysectomy, enzyme-associated granules were localized at the basal end of the cell and droplets were absent. Intravenous injection of TSH resulted in formation of droplets at the apical end of the cell and migration of enzyme-associated granules toward the apical end of the cell. The droplets were first observed approximately 10 minutes after TSH administration and at this time did not appear to contain enzyme. Within 15 minutes many droplets contained enzyme. The granules were largely localized near the nucleus on its apical side 30 minutes after a dose of 25 milliunits of TSH, but were less well localized following one-tenth this dose. These results indicate that the epithelial cell of the thyroid gland contains preformed hydrolytic enzymes associated with granules (lysosomes). When the gland is stimulated by TSH, droplets are formed from colloid derived from the lumen (phagosomes), and hydrolytic enzymes are transferred from granules to the droplets. The droplets may be intracellular organelles for hydrolysis of colloid and liberation of thyroxine prior to the release of thyroxine into the blood.

Acid Phosphatase↗
PubMed1963

A histochemical study of phagocytic and enzymatic functions of rabbit mononuclear and polymorphonuclear exudate cells and alveolar macrophages. I. Survey and quantitation of enzymes, and states of cellular activation.

The cytochrome oxidase (CO), aminopeptidase (AMP), succinic dehydrogenase (SD), acid phosphatase, esterase, and alkaline phosphatase of rabbit mononuclear (MN) and polymorphonuclear (PMN) peritoneal exudate cells and pulmonary alveolar macrophages (AM) - air dried on Mylar strips - were characterized by histochemical techniques with respect to stability, activators, inhibitors, and pH optima. A granule count method was established for the quantitation of these enzymes. For the acid phosphatase of MN, in which the most precise results were obtained, time, pH, substrate, and inhibitor curves resembled those commonly obtained biochemically. Five of these enzymes were usually more active in AM than MN, whereas the sixth, alkaline phosphatase, was not present in either cell type. AM also tended to consume more oxygen than MN and to divide more frequently. Since the most active cells in the population would be first involved in the host's defense against microbial agents, a comparison was made of the 10 per cent of the AM and MN with the highest enzymatic activities. No differences were found in the granule counts that were not reflected by the means. However, within a given AM population, cells containing ingested dust particles seemed to have higher enzymatic activities than those without particles. MN had greater acid phosphatase and SD activities than PMN and consumed more oxygen, but the CO, AMP, and esterase activites of both types of cells were of similar magnitude. PMN showed high alkaline phosphatase activity; MN showed none. A survey of the histochemical literature indicates that a positive correlation between the enzymatic and phagocytic activities of both MN and PMN exists in vivo.

Acid Phosphatase↗