The deposition of synthetic luteinizing hormone-releasing hormone (LRH), LRH inactive analogue, LRH agonist analogue and thyrotropin releasing-hormone (TRH) in small quantities in the immediate vicinity of neurons, via the technique of microelectrophoresis, has demonstrated the action of these peptides on the electrical activity of neurons throughout the brain. In each area of the central nervous system studied, from the cerebral cortex to the basal hypothalamus, neurons responded to the microelectrophoretic application of these peptides with excitation, or inhibition or failed to respond. The direction of the neuronal response to synthetic LRH and LRH agonist analogue was similar. In some cases, the analogue initiated a greater and longer-lasting effect. In neurons which were excited by LRH, TRH caused either a marked inhibition or no response. In general, the response of sensitive neurons to microelectrophoresis of peptides was produced with successive drug applications, yet there was no effect during application of current control. It is suggested that the presence of peptide-sensitive neurons in the central nervous system raises the possibility of a novel mechanism for chemical information transfer mediating anterior pituitary secretion and endocrine-related behaviour.
- neural activity
- peptide hormones
ASJC Scopus subject areas
- Cellular and Molecular Neuroscience