Priming in oxytocin cells and in gonadotrophs.

At proestrous, the sensitivity of gonadotrophs to gonadotrophin-releasing hormone (GnRH) increases with repeated exposure to GnRH, a process known as self-priming. An apparently similar phenomenon can also occur in peptidergic neurons; activity-dependent oxytocin release from dendrites can be potentiated by oxytocin itself. In the brain, such priming actions have the potential to alter the strength of communication between neuronal populations for a very prolonged period. In the case of both oxytocin neurons and gonadotrophs, priming appears to involve an augmentation of a readily releasable pool of vesicles.