LOCALIZATION OF ACETYLCHOLINESTERASE IN RAT MYOTUBES IN THE PRESENCE OF BETA-ENDORPHIN AND BETA-ENDORPHIN-(1-27)

In rat embryo skeletal myotubes, acetylcholinesterase is present, as multiple forms, and can be detected in deposits at the cell surface. Myotubes cultured in the presence of β-endorphin, exhibit an increased predominance of the globular (precursor) forms of the enzyme, which are largely restricted to intracellular sites associated with nuclei. In the presence of β-endorphin-(1-27), the relative proportions of the different forms of acetylcholinesterase is similar to that seen in the controls, but the enzyme is intracellular and has a characteristic focal localisation in the myotube. © 1990 Birkhäuser Verlag Basel.