Radioimmunoassay of brain peptides: Evaluation of a methodology for the assay of β-endorphin and enkephalin

Life SciencesPublished 1 September 1977

Jean Rossier, Alejandro Bayón, Therese Vargo, Nicholas Ling, Roger Guillemin, Floyd E. Bloom

DOI10.1016/0024-3205(77)90414-3

Source URL

Citations139

SJR quartileQ1

SJR score1.31

SNIP1.07

TL;DR

It is indicated that disruption of tissue modifies the content of opioid peptides in brain by being readily hydrolized by brain homogenates with consequent appearance of α-endorphin.

Abstract

The brain levels of β-endorphin, α-endorphin and enkephalin were measured by radioimmunoassay after different methods of sacrifice. Microwave irradiation proved not to be better than decapitation followed by boiling of the intact tissue, the latter procedure giving values of β-endorphin 10 fold higher than decapitation alone. Concurrently when decapitation was followed by boiling, α-endorphin was no longer detected. Evaluation in brain tissue of several extraction media--phosphate buffered saline, 5% TCA, HCl methanol, and 1N HOAc--showed the last to be the most satisfactory for both β-endorphin and enkephalin. Since β-endorphin was found to be readily hydrolized by brain homogenates with consequent appearance of α-endorphin, these results indicate that disruption of tissue modifies the content of opioid peptides in brain.

Keywords

Immunology and MicrobiologyNeuroscienceBiochemistry, Genetics and Molecular Biology

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