A simple method for examining organotypic CNS cultures with Nomarski optics

This paper describes a method for examination of living organotypic cultures of CNS with Nomarski differential interference-contrast optics. Cultures grown in Maximow assemblies, which promote the best differentiation of the tissue but are optically faulty, are transferred for Nomarski observation to a simple sandwich chamber which combines the optical perfection of the usual sandwich chamber with the flexibility and safeguarding of sterility characteristic of the Maximow assembly. Thus cultures can be transferred repeatedly between their maintenance and observation chambers. In the resulting microscopic images, it is possible to visualize delicate unmyelinated fibers, myelinated cell bodies and other features which are normally impossible to demonstrate in living cultures as well as to improve the images of other structures such as large neuronal perikarya and myelinated axons.