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M Cantin

Publications and source records attributed to M Cantin.

13 recordsLinked to original sources
PubMed1979

Metaplastic and mitotic activity of the ischemic (endocrine) kidney in experimental renal hypertension.

Partial ligation of the aorta between the renal arteries in the rat induces malignant hypertension, metaplasia of smooth-muscle cells of arterioles and arteries into juxtaglomerular cells, and a complex series of events in tubular cells at all levels of the ischemic kidney. The tubular cells of the outer cortex, particularly the proximal convoluted cells, show a very rapid and progressive simple atrophy. In contrast, necrosis of individual cells is followed by mitotic activity in atrophic tubular cells of the inner cortex, medulla, and papilla. Subsequently, polyploidy and hyperplasia occur in the inner cortex. At the same time, hypertrophy of the protein-synthesizing apparatus and an increase in protein, DNA, and RNA, followed by a decrease in the protein content, are seen in the tubular cells of the inner cortex. In the medulla and papilla, necrosis of individual cells proceeds side by side with waves of mitotic activity. These events take place, albeit to a lesser degree, even in cases of very mild renal ischemia. While they may by unrelated to hypertension, these changes are probably involved in the increase in hydrolytic enzyme activity characteristic of the ischemic renal cortex.

Animals↗
PubMed1979

[Ultrastructural cytochemistry of the mouse juxtaglomerular apparatus (author's transl)].

The ultrastructural cytochemistry of the mouse juxtaglomerular apparatus has been studied. The specific granules of the juxtaglomerular cells were found to be argentaphobic when ultrathin sections of araldite-embedded renal cortex were stained according to the periodic acid-thio-carbohydrazide-silver proteinate technique of Thiery. This technique revealed an abundant glycogen of type beta in the specific granules and in the cytosol of these cells. The rim of specific granules was positive when ultrathin sections of glutaraldehyde-fixed, glycol methacrylate-embedded kidneys were stained with phosphotungstic-hydrochloric acids at a low pH. A reaction was also shown by the cell coat, lysosomes, autophagolysosomes, residual bodies and part of the Golgi complex. These results indicate that the specific granules of the mouse juxtaglomerular apparatus contains glycoproteins that are glycosylated in the Golgi complex.

Animals↗
PubMed1977

Ultrastructural cytochemistry of the human adrenal medulla.

A cytochemical study of the human adrenal medulla showed that it is made up of two types, the adrenaline (A-) and noradrenaline (N-) storing cells. A-and N-storing granules were argentaphobic when ultra-thin sections of Araldite-embedded medulla were stained according to the periodic acid-thiocarbohydrazide silver proteinate technique of Thiery. A small amount of glycogen (which disappeared after digestion with alpha amylase) in the form of B-particles, as well as lysosomes were, however, visualized by this technique. The entire core of A granules was markedly positive after ultrathin sections of glutaraldehyde-fixed, glycol methacrylate (GMA-) embedded medullae were stained with phosphotungstic acid (PTA) at a low pH (O.3). The N granules, in contrast, were mostly unreactive. PTA stained a large part of the Golgi complex of A cells, whereas it generally had no such effect on that of the N cells. In both cell types, the cell coat, lysosomes and multivesicular bodies reacted to PTA. The periodic acid schiff (PAS) technique showed A but not N granules in semithin sections of GMA-or Araldite-embedded medullae. The PTA and PAS stains were abolished by acetylation, restored by saponification, unchanged by methylation and greatly diminished by sulfation or by digestion with beta glucuronidase after oxidation by perchloric acid. These results indicate that in man the A granules and the Golgi complex of A cells, unlike the same structures in N cells, are rich in glycoproteins.

Adrenal Medulla↗
PubMed1975

Localization and characterization of carbohydrates in adrenal medullary cells.

The localization and characterization of carbohydrates in adrenal medullary cells were studied by histochemical and cytochemical methods. Adrenaline (A)-and noradrenaline (N)-storing granules were argentaphobic when ultrathin sections of Araldite-embedded medullae were stained according to the periodic acid-thiocarbohydrazide-silver proteinate technique of Thiery. A small amount of glycogen in the form of single beta-particles as well as lysosomes were, however, visualized by this technique. The entire core of the A granules was markedly positive after ultrathin sections of glutaraldehyde-fixed, glycol methacrylate (GMA)-embedded medullae were stained with phosphotungstic acid (PTA) at low pH (0.3). The N granules, in contrast, were mostly unreactive. In the A cells, PTA stained a large part of the Golgi complex, whereas in the N cells the Golgi complex was mostly unstained. In both cell types, the cell coat, lysosomes, and multivesticular bodies reacted to PTA. The periodic acid-Schiff (PAS) technique showed A but not N granules in semithin sections of GMA- or Araldite-embedded medullae. The PTA and PAS stains were abolished by acetylation, restored by saponification, unchanged by methylation, and greatly diminished by sulfation. In ultrathin sections of GMA- or Araldite-embedded medullae incubated with colloidal iron according to various techniques, the cell coat and lysosomes of both cell types were stained, unlike all the other cytoplasmic organelles. These results indicate that A granules and the Golgi complex of A cells, unlike the same structures in N cells, are rich in glycoproteins which are probably not acidic.

Adrenal Medulla↗
PubMed1975

Comparative ultrastructural cytochemistry of juxtaglomerular cell granules and renal tubular cell lysosomes.

Because of certain similarities in morphology and function between juxtaglomerular cell granules and renal tubular cell lysosomes, the cytochemistry of both of these structures was compared. Juxtaglomerular cell granules and renal tubular cell lysosomes were found to be argentaphobic when ultrathin sections of Araldite-embedded kidneys were stained according to the periodic acid-thiocarbohydrazide-silver proteinate technique of Thiéry (Thiéry, J. P. J. Microsc. (Paris) 6: 987, 1967 and J. Microsc. (Paris) 8: 689, 1969). The rim of both structures was moderately positive when ultrathin sections of glutaraldehyde-fixed, glycol methacrylate-embedded kidneys were stained with phosphotungstic acid at a low pH. A reaction was also shown by the cell coats, residual bodies and, in proximal convoluted tubules, by the Golgi complex. In ultrathin sections of either glycol methacrylate- or Vestopal-embedded renal cortex stained by various methods with colloidal iron, juxtaglomerular cell granules were negative whereas renal tublar cell lysosomes were intesely positive. Colloidal iron also stained the cell coats of both justaglomerular and tubular cells. These results indicate that both juxtaglomerular cell granules and renal tubular cell lysosomes contain glycoproteins which are not acidic in the former and are acidic in the latter.

Animals↗
PubMed1975

Chemical nature of atrial specific granules.

The specific granules are argentafugic when ultrathin sections of Araldite-embedded atria are stained according to the periodic acid-thiocarbohydrazide-silver proteinate technique of Thiery. The entire core of the atrial specific granules is moderately positive after ultrathin sections of glutaraldehyde-fixed, glycol methacrylate- (GMA-) embedded atria are stained with phosphotungstic acid at a low pH. A similar reaction is shown by the cell coat, intercalated discs, residual bodies (C-granules), and Z-discs, as well as by a very small portion of the Golgi complex. Analogous results are obtained with semithin sections of GMA- embedded atria stained according to the periodic acid-Schiff (PAS) technique. In ultrathin sections of GMA-embedded atria stained with dialyzed colloidal iron (DI), the cell coat of the cardiocytes is positive, unlike all the other cytoplasmic organelles. When ultrathin sections of GMA-embedded atria are incubated with proteolytic enzymes (pronase, pepsin, or trypsin), atrial specific granules and Z-bands and, to a much lesser degree, cell coat and sarcolemma are selectively digested. Proteins are also distinctly demonstrated in the paranuclear specific granules by a variety of histochemical techniques. These results indicate that atrial specific granules are rich in proteins and possess a weak complement of complex carbohydrates.

Animals↗
PubMed1975

The chemical nature of human atrial specific granules.

The nature of human auricular specific granules was assessed by a variety of cytochemical and histochemical methods. The specific granules were found to be argentaphobic when ultrathin sections of Araldite-embedded auricular appendages were stained according to the periodic acid-thiocarbohydrazide-silver proteinate technique of Thiery. The entire core of these granules was moderately positive after ultrathin sections of glutaraldehyde-fixed, glycol methacrylate (GMA)-embedded auricles were stained with phosphotungstic acid (PTA) at a low pH. A similar reaction was shown by the cell coat, residual bodies (C-granules), lysosomes, Z-discs as well as by a very small portion of the Golgi complex. Analogous results were obtained in semithin sections of GMA-embedded auricles stained by the periodic acid-Schiff (PAS) technique. Incubation of ultrathin sections (fixed in glutaraldehyde and embedded in GMA) with proteolytic enzymes (pronase, pepsin, trypsin, or alpha-chymotrypsin) elicited selective digestion of atrial specific granules and Z-bands and, to a much lesser degree, of the cell coat. It is concluded that human auricular specific granules, as in rat atrial cardiocytes, are composed mostly of proteins. In addition, these granules may contain complex carbohydrates.

Chemical Phenomena↗