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Unfixed cryostat or cold Formal calcium/gum sucrose fixed.


Solution a

--L-leucine-4-methoxy-p-naphthylamide stock

--L-leucine-4-methoxy-p-naphthylamide 4mg

--Ethanol 0.1ml

--Distilled water 4.9ml

Incubating solution

--solution a 0.5ml

--0.85% sodium chloride (425mg/50ml) 4.0ml

--0.00005M potassium cyanide (65mg/50ml) 0.5ml

--Fast blue B salt 5mg

--0.1M acetate buffer pH 6.5 5ml


1. Incubate in solution b. for 15-120 minutes at room temperature.

2. Rinse in 0.85% sodium chloride for 2 minutes.

3. Immerse in 0.1M copper sulphate (798mg/100ml) for 2 minutes.

4. Rinse in 0.85% sodium chloride for 2 minutes.

5. Wash, counterstain in haematoxylin, wash.

6. Dehydrate, clear . Mount sections in DPX


Leucine-amino peptidase activity - Red


Sections may be counterstained in 2% methyl green L leucyl-B-naphthylamide may be employed as a the substrate, but with inferior results.

CONTROLS: Small and large intestine, kidney.

NOTE: No responsibility is assumed by The University of Nottingham or the Queens Medical Centre NHS Trust for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions or ideas contained in the material herein. It is the users responsibilty to ensure that all procedures are carried out according to appropriate Health and Safety requirements.

© Copyright 1997 University of Nottingham Medical School Division of Histopathology. This page was last built on Mon, May 5, 1997 with Frontier. Thanks for looking in. Comments to James.Lowe@nottingham.ac.uk