HMGCR and obesity due to melanocortin 4 receptor deficiency: In contrast, an elevation of the adipocyte cholesterol amount has also been reported in obese rodents and humans [43,46] and studies using ob/ob mice show increased HMGCR activity in adipose (but not liver) and higher plasma cholesterol in young obese mice compared to control littermates, suggesting an adipocyte-specific regulation of cholesterol metabolism in obesity [8,47].