Relationship of α-MSH and AgRP axons to the perikarya of melanocortin-4 receptor neurons

Add time:07/12/2019    Source:sciencedirect.com

The central melanocortin system is composed of neurons that express either the proopiomelanocortin (POMC) or the agouti-related protein (AgRP). POMC is cleaved in bioactive peptides, including the α-melanocyte-stimulating hormone (α-MSH). α-MSH activates the melanocortin-4 receptor (MC4R) inducing satiety, whereas AgRP acts as an inverse agonist of MC4R. However, only limited information is available regarding possible area-specific differences in the interaction between α-MSH and AgRP terminals on MC4R-expressing cells. Therefore, the objective of the present study was to compare the distribution pattern of α-MSH and AgRP terminals on the perikarya of MC4R-expressing neurons. We performed a triple-label immunofluorescence reaction in brain series of MC4R-reporter mice to visualize MC4R-expressing neurons together with AgRP and α-MSH terminals. POMC and AgRP neurons project to areas that contain MC4R-expressing cells, although several brain nuclei exhibit AgRP and α-MSH terminals, but they do no express MC4R, while other brain areas contain MC4R-expressing cells and receive no apparent innervation of AgRP and POMC neurons. AgRP terminals make more presumptive appositions than α-MSH on the soma of MC4R-expressing neurons of the medial preoptic area and paraventricular nucleus of the hypothalamus (Pa). Additionally, a higher percentage of MC4R cells receive at least one presumptive apposition from AgRP terminals in the median preoptic nucleus and Pa, compared to α-MSH appositions. Thus, our study revealed area-specific differences in the interaction between α-MSH and AgRP terminals and the soma of MC4R-expressing neurons. These findings provide new insights about the relationship between first- and second-order neurons of the central melanocortin system.

We also recommend Trading Suppliers and Manufacturers of MSH, beta, (6-8) (cas 85775-46-8). Pls Click Website Link as below: cas 85775-46-8 suppliers

Prev:Quantitative mass spectrometry for human melanocortin peptides in vitro and in vivo suggests prominent roles for β-MSH and desacetyl α-MSH in energy homeostasis
Next:The orphan G protein-coupled receptor GPR139 is activated by the peptides: Adrenocorticotropic hormone (ACTH), α-, and β-melanocyte stimulating hormone (α-MSH, and β-MSH), and the conserved core motif HFRW)