Amperometric recording of gonadotropin-releasing hormone release activity in the pituitary of the dwarf gourami (teleosat) brain-pituitary slices

We developed a method for real-time electrochemical recording of gonadotropin-releasing hormone (GnRH) release using carbon fiber electrodes (CFE). The oxidation current of GnRH was measured by amperometry. We recorded the release activity in the pituitary of the teleost brain-pituitary slice. The CFE was located in the part of the pituitary that receives dense innervation from GnRH neurons in the preoptic area. A bulk amperometric current was recorded in response to high [K +] o stimulation in a dose dependent manner. Decreasing the holding potential to below the oxidation potential of GnRH resulted in the loss of amperometric currents. Thus, it is suggested that the amperometric currents are mainly attributed to the oxidation currents of GnRH and reflect the GnRH release activity.