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W F Cook

Publications and source records attributed to W F Cook.

9 recordsLinked to original sources

The histochemical localisation of aminopeptidases in the central nervous system and an analysis of factors contributing to the final staining pattern.

A method is described for the localisation of aminopeptidases in the central nervous system. The enzymatic cleavage of the peptide bond in the substituted naphthylamide substrates results in the liberation of free naphthylamine which in the presence of an azo salt can be precipitated as a blue dye at sites of enzyme activity. Analysis of different brain regions using this technique indicates that these enzymes may have a specific function at certain sites in the CNS. Since this is the first method to produce any localised staining in nervous tissue an analysis of factors contributing to the final staining pattern is also presented.

2-Naphthylamine

The preparation of rabbit renin-substrate for the assay of minute amounts of renin.

1. By DEAE-cellulose chromatography and treatment with Cd(2+) a partially purified renin-substrate has been prepared from rabbit serum. 2. It has the following properties: (a) Angiotensinase activity is undetectable: 0.1mug. of angiotensin was recovered intact after incubation with the substrate at 37 degrees for 200hr. (b) It does not contain renin and does not generate vaso-active substances when incubated alone. (c) It is ten times as active as serum in terms of angiotensin produced/mg. of protein. (d) It has not deteriorated after storage for 3 months at 4 degrees at pH7.5.

Angiotensin II