The Expression of Fos, Jun and AP-1 DNA Binding Activity in Rat Supraoptic Nucleus Neurons Following Acute Versus Repeated Osmotic Stimulation
Abstract:
FOB and Jun are protein products of their respective proto-oncogenes, c-fos and c-jun. Nuclear concentrations of both proteins rapidly, but transiently, rise after thepresentation of a variety of stimuli under in vitro and in vivo conditions. Fos and Jun can form heterodimeric proteins that act as transcription factors to regulate late response genes.Previous work has demonstrated that hypertonic saline injection results in Fos expression in supraoptic nucleus SON neurons that mediate body water homeostasis. Since Fos is thought to act mostly in conjunction with Jun, I first developed a double-label fluorescence immunocytochemical procedure that permits simultaneous visualization of neurons expressing Fos and Jun. After hypertonic saline administration, the immunostaining of c-Fos and c-Jun was coexistent in the majority of rnagnocellular neurons of SON.