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B J Pirie

Publications and source records attributed to B J Pirie.

7 recordsLinked to original sources
PubMed1986

Some effects of selenium deficiency on glutathione peroxidase (EC 1.11.1.9) activity and tissue pathology in rainbow trout (Salmo gairdneri).

1. Two duplicate groups of rainbow trout (Salmo gairdneri; mean weight 27 g) were given diets of differing selenium content (deficient 0.025 mg Se/kg; supplemented 1.022 mg Se/kg) for 30 weeks. 2. There were no significant differences between treatments in weight gain but packed cell volume, liver vitamin E and liver and plasma Se concentrations were all significantly lower in the Se-deficient trout. 3. Ataxia occurred in about 10% of the Se-deficient trout and histopathologies were evident in nerve cord (damage to axon sheath) and liver (loss of integrity in endoplasmic reticulum and mitochondria with appearance of increased vesiculation). 4. Glutathione peroxidase (EC 1.11.1.9) activity was significantly reduced in liver and plasma of Se-deficient fish but there was no indication, from differential assay, of any non-Se-dependent glutathione peroxidase activity. Glutathione transferase (EC 2.5.1.18) activity was significantly increased in Se-deficient trout.

Animals↗
PubMed1979

The occurrence of cadmium in sub-cellular particles in the kidney of the marine mussel, Mytilus edulis, exposed to cadmium. The use of electron microprobe analysis.

In mussels (Mytilus edulis) chronically exposed to cadmium, 85% of the Cd2+ was found to be associated with membrane-limited granular structures when elemental analyses were carried out on cryo-sectioned tissue by electron probe X-ray microanalysis. These granules also contained high concentrations of sulphur and phosphorus as well as other metalions, including Ca2+, iron and Zn2+. In contrast, after homogenisation and fractionation by differential centrifugation, the major proportion of the Cd2+ was found in the cytoplasmic fraction. However, many lysosomes were also ruptured by this treatment. Gel filtration chromatography of this fraction indicated the presence of a Cd2+-binding component of similar molecular weight to the metallothionein purified from the digestive gland of the same animals. It is therefore proposed that metallothionein may be associated with particulate structures which would thus reduce its cellular toxicity.

Animals↗
PubMed1979

An electron microscopic study of lipid absorption in the pyloric caeca of rainbow trout (Salmo gairdnerii) fed wax ester--rich zooplankton.

Rainbow trout were killed 4 and 18 h after being fed wax ester-rich marine zooplankton and the absorptive epithelium of the pyloric caeca examined by electron microscopy. Numerous osmiophilic drops were seen in the lamina propria underlying the epithelium of fish killed at both times, but these drops were only abundant within columnar epithelial cells of fish killed 4 h after feeding. Pinocytotic profiles were not common at the luminal plasma membranes, nor were osmiophilic droplets seen in the terminal web area between the luminal plasma membrane and the extensive smooth endoplasmic reticulum. Numerous osmiophilic droplets, 30--100 nm in diameter, were present in the cisternae of the smooth endoplasmic reticulum with up to five separate droplets per individual cisterna. Columnar epithelial cells also contained up to 100 large osmiophilic drops ("conglomerates") which tended to be concentrated in the supranuclear (Golgi) regions. The conglomerates were 250--1200 nm in diameter and were themselves made up of smaller droplets 30--400 nm in diameter. Conglomerates were present both within intracellular membranes and free in the cytoplasm. Osmiophilic droplets in the intercellular spaces and lamina propria were similar in size to individual droplets within conglomerates. We conclude that triacylglycerols are elaborated in the smooth endoplasmic reticulum, transferred to and processed in the Golgi region and finally discharged serosally as chylomicron-like particles of not greater than 400 nm diameter.

Animals↗