title: Characterization of electrophoretically separable endorphins in human CSF.
abstract: Opioid peptides have been purified from large pooled samples of human cerebrospinal fluid. The purification steps involved chromatography on Sephadex G-10 and electrophoresis in agarose suspension. The purified material was further characterized by HPLC and radioimmunoassay. All procedures were guided by a specific radioreceptor assay. The Sephadex G10 fractionation yielded receptor activity in two discrete fractions, Fraction I (FI) and Fraction II (FII). A second Sephadex run of FII gave a partial resolution of two components, one of which was larger (FIIA). Electrophoresis resolved these fractions into several components, most of which showed a more basic behaviour than the enkephalins. Thus, FI separated into at least 4 components and FIIB into two components while FIIA remained a single peak. These components appeared to migrate as distinct peaks and some of them also chromatographed on a HPLC-column as single components. Considering their behaviour in electrophoresis and on HPLC, two components are suggested to represent known endorphin structures. The predominant FII component (FIIA) was thus indistinguishable from Met-enkephalin-Lys6 in all chromatographic systems and one of the most basic FI components showed close similarity with dynorphin. Each of these components occurs at a higher concentration than Met- or Leu-enkephalin, dynorphin or beta-endorphin.
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004399:Dynorphins; D004587:Electrophoresis, Agar Gel; D004723:Endorphins / Q000134:cerebrospinal fluid*; D004743:Enkephalin, Leucine / Q000134:cerebrospinal fluid; D004744:Enkephalin, Methionine / Q000134:cerebrospinal fluid; D006801:Humans; D011863:Radioimmunoassay; D001615:beta-Endorphin
chemical_list: D004723:Endorphins; D004744:Enkephalin, Methionine; D004743:Enkephalin, Leucine; D001615:beta-Endorphin; D004399:Dynorphins