Methods for the isolation of viable gonadotropin-releasing hormone (LRF) neurons

Studies were conducted in order to determine if selected neurons could be isolated from the brain using Sepharose-linked recognition complexes directed against or related to the biosynthetic/neurosecretory product of the desired neuronal population. Immunoreactive LRF neurons were precipitated when dispersed cells of adult male rats were incubated successively in media containing free LRF antiserum followed by the exposure of LRF bound to Sepharose-4B. The radioimmunoassayable LRF content of the isolated cells was 88% of that contained in fresh frozen tissue of a contemporary group of rats and trypan blue exclusion indicated that at least 85% of the neurons were viable. Furthermore, based on immunocytochemistry and cresyl violet staining in combination with immunocytochemistry, the isolated cell fraction appeared to be free from other types of cells and also exhibited assayable LRF release when challenged with potassium. These results suggest that the neuroendocrine properties of hypothalamic neurons may be exploited in order to isolate viable cells for acute in vitro experiments.