GROWTH hormone-releasing hormone (GHRH) and β-endorphin are mainly synthesized in neurones of the hypothalamic arcuate nucleus. Arcuate neurones also contain both ionotropic and metabotropic glutamate receptors. The aim of present study was to investigate whether glutamate receptors are present in GHRH and β-endorphin containing nerve cells of this hypothalamic area. Using double-label immunocytochemistry as well as the mirror technique, we found that almost all GHRH and β-endorphin immunoreactive arcuate neurones contain the metabotropic glutamate receptor 1a. The observations provide morphological evidence for the view that glutamate, which appears to be a major excitatory neurotransmitter in the hypothalamus, may directly stimulate GHRH and β-endorphin neurones of the medial hypothalamus.
- Arcuate nucleus
- Growth hormone-releasing hormone
- Metabotropic glutamate receptor
ASJC Scopus subject areas