MYLK and obesity due to melanocortin 4 receptor deficiency: This study investigated the impact of high-fat diet (HFD)-induced obesity on endothelium-dependent relaxation function and explored the potential role of myosin light chain kinase (MLCK) signaling in a rabbit model.<h4>Methods</h4>Forty-five male New Zealand White rabbits were randomized into control (normal diet), HFD, and ML-7 (HFD plus the MLCK inhibitor ML-7, 1 mg/kg/day) groups (<i>n</i> = 15/group).