Ultrastructural Pathology of the Cell and Matrix by Feroze N. Ghadially

Author:Feroze N. Ghadially [Ghadially, Feroze N.]
Language: eng
Format: epub
ISBN: 978-1-4831-9208-6
Publisher: Elsevier Science
Published: 1988-03-14T05:00:00+00:00

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*On the basis of serial section studies, Daems and Wisse (1966) concluded that in mouse hepatocyte mitochondria, cristae are attached to the inner mitochondrial membrane by rounded stems which they call ‘pediculi cristae’

†Such an appearance is seen when a mitochondrion is about to divide. (See Plate 95, Figs. 1 and 2 and Plate 133, Fig. 3. See also page 216 and footnote on page 244.)

*Cell types which have abundant rough endoplasmic reticulum usually have little smooth endoplasmic reticulum, and vice versa. An exception to this is the hepatocyte, where both forms of endoplasmic reticulum are fairly well represented and continuities between the two can be demonstrated. It is interesting to note that an occasional tubular crista is seen among the lamellar cristae in hepatocyte mitochondria.

*The differences between undulating and pouched membranes are explained in a footnote on page 94.

*Mitochondrial cristae are absent in certain petite mutant strains of yeast which completely lack mitochondrial DNA. However, the inner and outer membranes of the mitochondrion are not altered (Montisano and James, 1979). This suggests that the inner membrane can be produced under the control of nuclear DNA, but not the cristae.

*Estimates of the half-life of rat mitochondria are: (1) liver, 9.6-10.3 days; (2) kidney, 12.4 days; (3) adrenal cortex, 8.2-11.5 days (Fletcher and Sanadi, 1961; Wilson and Dove, 1965; Mazzocchi et al., 1976).

†Mitochondrial pyknosis must not be confused with mitochondria showing a condensed configuration. Compare Plate 96with Plates 108, 109 and 111.

*This is a relatively non-destructive form of analysis by which elements from Na upwards (i.e. above Z number 10) can be simultaneously detected and displayed as a spectrum. The best spatial resolution that can be obtained is of the order of 20nm. The sensitivity of detection varies with the elements but is of the order of 10-18g. It is the only way of analysing minute inclusions in situ within the cell and so correlate morphology with atomic composition. (For a reviewsee Ghadially, 1979a.)

†With energy dispersive spectrometry it is difficult to convincingly demonstrate small amounts of phosphorus in osmicated tissue because of the proximity of the M peak of osmium (1.914 ke V) and the Kα peak of phosphorus (2.012 keV). The resolution of the x-ray detector is usually only about 150eV so peaks separated by an interval of only 99 eV are not well resolved.

‡See Chandler (1977) and Morgan (1979) for succinct accounts on how conventional wet chemical preparative techniques disturb the in vivo chemical integrity of biological tissues.

§For example commercial glutaraldehyde contains calcium (Oschman and Wall, 1972). Distilled glutaraldehyde is free from this defect.

*The controversy about the composition and function of matrical dense granules seems to be unending. Biochemical analysis of isolated granules by Brdiczka and Barnard (1980) suggest that they are composed of phospholipoprotein and that under some in vitro conditions this lipoprotein can bind calcium. Regarding the function of these granules in vivo, Fawcett (1981) feels that in most sites they are probably not involved in calcium sequestration but they may be involved in this activity in mineralized tissues.

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