Homocysteate and homocysteine sulfinate, excitatory transmitter candidates present in rat astroglial cultures

The presence of homocysteate and homocysteine sulfinate was demonstrated in extracts prepared from cultures of rat cortical and cerebellar astrocytes as well as from C6 glioblastoma cells by o-phthalaldehyde derivatization and subsequent HPLC analysis. Homocysteate-like immunoreactivity was found in cultured cortical astrocytes by postembedding immunocytochemistry at the level of light microscopy. These findings support the notion of a glial localization of the excitatory transmitter candidate homocysteate.