Application Cholera toxin B subunit conjugated to peroxidase (CB-HRP) has been shown to be a more effective retrograde and transganglionic tracer for pelvic primary afferents from the urinary bladder than wheat germ agglutinin-horseradish peroxidase or isolectin B4-horseradish peroxidase. Retrograde labeling with CB-HRP has been demonstrated in symphathetic pre-ganglionic neurons as well as in cells of the fastigial nuclei. It is also an effective anterograde tracer for the study of axonal and terminal labeling in brain stem. Packaging Vial contains approx. 42 μg cholera toxin B subunit, conjugated to 100 μg (10-30 units) horseradish peroxidase, and buffer salts from 0.1 mL of 0.01 M sodium phosphate, pH 7.5. Reconstitution Reconstitute with 0.1 mL water Unit Definition One unit will form 1.0 mg of purpurogallin from pyrogallol in 20 sec at pH 6.0 at 20 °C. Biochem/physiol Actions The cholera toxin B subunit is used for track tracing in neurological research, taking advantage of GM1 ganglioside binding and retrograde transport. Tissue culture cells treated with cholera toxin are not killed and tissues of animals do not become necrotic. |