Improved post-embedding immunocytochemistry of myelinated nervous tissue for electron microscopy

The particularly high lipid content of normal mature adult myelin sheaths, together with the light fixation protocols usually necessary to retain anti genicity, combine to make white matter nervous tissue an especially problem atical subject for post-embedding immune-electron microscopy using modern a crylic resins. Fixation and infiltration modifications to standard processi ng schedules for Lowicryl were found to greatly improve the embedding and t herefore the resulting morphology. This in turn improved the signal to nois e ratio by reducing the high non-specific backgrounds usually found in poor ly infiltrated areas. Using Lowicryl HM20, we have been able to obtain sati sfactory immunostaining for myelin basic protein with good retention of str uctural integrity in the myelin of both normal and lesioned adult cortico-s pinal tract. (C) 2000 Elsevier Science B.V. All rights reserved.