Figure 5. Intra‐VMH microinjection of the mixed melanocortin receptor agonist MTII elevates mRNA expression of mediators of energy expenditure in peripheral metabolic tissues, with some alteration in the protein content and phosphorylation .

Relative to vehicle‐treated rats, rats with intra‐VMH melanocortin receptor activation had significantly elevated mRNA levels of UCP2 and 3, SERCA2 and PPARδ in the (A) quad and (B) gastroc muscles; quad also had significantly elevated SERCA1, whereas gastroc showed higher β₂ adrenergic receptor (Beta 2) and PPARα and δ expression and lower expression of the Kir6.2 subunit of the ATP‐gated K⁺ channel. C, liver of MTII‐injected rats showed elevated expression UCP2 and PPAR isoforms α, δ, and γ. D, BAT showed elevated expression of UCP1 and PPAR isoforms α, δ and γ in MTII‐injected rats. E, western blots were used to measure protein and phosphoprotein expression levels. In MTII‐treated rats, the pAMPK‐to‐AMPK ratio was significantly elevated in (F) quad, (G) gastroc, (H) liver, (I) BAT and (J) WAT, whereas the pACC/ACC ratio was significantly elevated above vehicle‐treated levels in muscle and BAT only. Mean vehicle‐treated defined as 100%. ^*Intra‐VMH MTII‐injected rats vs. vehicle‐treated rats, P < 0.05. (n = 7 per group for mRNA, four or five per group for protein).