Validation of an immunoassay for canine thyroid-stimulating hormone and changes in serum concentration following induction of hypothyroidism in dogs.

Objective: To validate a new immunoradiometric assay for canine thyroid-stimulating hormone (cTSH) and to document changes in serum cTSH concentration during induction of hypothyroidism in dogs.

Animals: Six healthy adult male Beagles.

Procedure: Sensitivity, specificity, precision, and accuracy of the cTSH assay were evaluated in vitro.

Hormonal effects on kallikrein, esterase A2, and their inhibitors in rat urine.

The effects of various hormones on the urinary excretion of kallikrein and esterase A2 were studied in rats. Chronic treatment with antidiuretic hormone had no effect on the excretion of either enzyme. Deoxycorticosterone treatment or a low sodium diet stimulated urinary kallikrein excretion (as is well known), but had no effect on urinary esterase A2.

Isolation and partial characterization of rat urinary esterase A2.

An enzyme, esterase A2, which hydrolyzes tosyl-arginine methyl ester was isolated from the urine of female, inbred, Dahl-salt-resistant rats using DEAE-Sephadex ion-exchange, aprotinin-agarose affinity and molecular sieve column chromatography. The purest preparation obtained showed four closely migrating bands on polyacrylamide gel electrophoresis. All four bands of the esterase A2 preparation had enzyme activity since all were stainable on zymograms using N-acetyl-L-methionine alpha-naphthyl ester as substrate.

Alteration in immune complex glomerulonephritis by arachidonic acid.

We employed a model of immune complex glomerulonephritis produced in mice by the daily injection of apoferritin to study the effect of treatment with arachidonic acid (AA). Apoferritin injections produced demonstrable glomerular damage by light microscopy associated with deposition of immunoglobulin along peripheral capillary loops. Treatment with AA 100 micrograms daily resulted in significantly less glomerular damage and a shift inthe location of immune complex deposition to the mesangium.