, Volume 40, Issue 2, pp 137-154

Peroxisomes in the liver of the carp (Cyprinus carpio L.) electron microscopic cytochemical and biochemical studies

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Summary

Hepatocytes of carps are investigated during the time from October to June. Morphological examinations reveal the occurrence of abundant single membrane bound organelles, 0.2 to 0.75 μm in diameter. These particles are of irregular round, oval or elongated shape. They show a matrix of moderate electron density and coarse granular substructure. A noncrystalline but dense core is observed very rarely.

Incubation of glutaraldehyde fixed tissue in alkaline (pH 9.0) medium containing 0.2% 3,3′ diaminobezidine and 0.02% H2O2 results in dense staining of these particles. The histochemical staining reaction is due to peroxidatic activity of catalase, since it is abolished by the addition of 2×10−2 M 3-amino-1,2,4-triazole. The organelles do not react for acid phosphatase activity. They are interpreted to represent peroxisomes.

Biochemical examinations indicate that all peroxisomal enzymes investigated (catalase, urate oxidase, D-amino-acid oxidase, L-α-OH-acid oxidase) are present in the mitochondrial, lysosomal and microsomal fraction prepared from carp liver homogenates by differential centrifugation methods. Pellets of every fraction are controlled morphologically as well as histochemically. In particular, catalase activity is demonstrated in membrane bound particles which sediment with the microsomal fraction. This finding is discussed with special reference to the problem if small type peroxisomes (microperoxisomes) represent true peroxisomal systems.

Supported by a grant of “Hochschuljubiläumsstiftung der Stadt Wien”.