Electrophysiological Analysis of Neuroendocrine Neuronal Activity in Hypothalamic Slices

We have described the use of the hypothalamic slice preparation in studying the membrane properties of the parvocellular neurosecretory neurons in situ as it relates to cell firing and hormone release. Stable intracellular recordings for up to 6 hr offer the possibility of doing extensive pharmacological testing to determine specific receptor subtypes and second messenger cascades that are associated with activation of these receptors. Moreover, slices from adult animals are utilized such that synaptic plasticity in afferent pathways can be studied. Most importantly, following the electrophysiological and pharmacological analysis of individual neurons, it is possible to identify the cell phenotype with intracellular biocytin followed by immunocytochemistry. We are currently developing an in situ hybridization technique in order to identify a greater number of different phenotypes within the heterogenous population of arcuate neurons.