High level of MCHR1 is found in the shell of the nucleus accumbens, an area involved in reward-related behaviour. Interestingly, the highest expression is observed in extrahypothalamic areas anterior olfactory nucleus, piriform cortex and olfactory tubercle. MCHR1 is highly expressed in the cerebral cortex, basal ganglia, hypothalamus, and brainstem. This cascade induces changes in cell proliferation and gene transcription. While, Gi activation causing decreased amount of cAMP (red arrows), Gq resulting in increased mitogen-activated protein kinase (MAPK) activity (blue arrows) via Ras and elevation of intracellular calcium level (mediated by inositol trisphosphate (IP3) and phospholipase C (PLC) activation). MCH binding to receptors leading to G protein coupling (Gs, Gi, Gq). Signalling pathways of melanin-concentrating hormone receptor 1 (MCHR1) (left panel) and MCHR2 (right panel). Reviewing the current knowledge on MCH system in human, rodents and avians may stimulate a new wave of studies in the field. Pharmacological modulation of MCH system could contribute to the therapy of eating disorders and improve agricultural efficiency regarding avians. In birds the MCH system especially in the lateral and basal hypothalamus has important connections to the limbic system and it coordinates the vegetative and endocrine functions, as well as the emotional behaviour. Several studies have proved the significance of MCH in obesity, diabetes and depression.Īlthough the peptide is well-characterized in mouse models, much less is known about its functions in avians. In mammals MCH increases food intake, contributes to regulation of energy balance, temperature, reproductive function, endocrine homeostasis and biological rhythms. MCH is located in the lateral and dorsal hypothalamus, as well as in the zona incerta. Melanin-concentrating hormone (MCH) is a cyclic 19 amino acid orexigenic hypothalamic peptide.

Mch neurons mouse brain