Cadmium/zinc relationships in kidney cortex and metallothionein of horse and red deer: histopathological observations on horse kidneys.

This research article investigates the relationship between Cadmium and zinc levels in the kidney cortex of horses and red deer. The study also presents an analysis of the influence of Cadmium content in horse kidneys on histopathological observations.

Measurement and Analysis

• The study involved determining Cadmium and zinc levels in the kidney cortex of 63 horses and 51 red deer. In doing so, they used protein fractions that were obtained through Sephadex chromatography of the kidney cortex from a subset of 10 horses and 4 red deer.
• The researchers compared certain histopathological parameters – factors suggesting diseased state in tissue examination – in the kidney cortex of horses to the Cadmium content.

Findings

• The metal content of horse kidney cortex showed that it generally contained 0.31 mmole Cadmium/kg and 0.63 mmole Zinc/kg. The Zinc level was observed to increase with Cadmium content, although this increase was reduced at higher concentrations.
• No significant increase in Cadmium content was observed with the age of the horses, which ranged between 2 to 19 years old.
• The kidney cortex of the red deer showed 0.030 mmole Cadmium/kg and 0.51 mmole Zinc/kg on average. In this case, the Zinc content did not increase with the Cadmium content. In contrast to horses, there was a positive linear relationship between the Cadmium content and the age of the deer, which ranged from 0 to 11 years old.
• In the protein fractions – metallothioneins – of horse kidney cortex, the molar Zinc/Cadmium ratio was less variable at higher Cadmium contents.
• All Cadmium and the increase in Zinc above an average basal level of 0.36 mmole Zinc/kg was discovered in the metallothionein fractions.

Pathological Observations

• The researchers did not identify any gross histopathological changes in the kidney cortex of the horses. However, a slight increase was noticed in the thickness of the basement membrane of Bowman’s Capsule and the diameter of Bowman’s Capsule, in relation to the Cadmium content up to 0.3 mmole/kg.