Seeing as the most well-defined regulator of traditional PRL expression in the pituitary is dopamine, which sharply inhibits its expression17 the paradoxical finding in this study that adrenergic hormones upregulated ePRL expression, necessitates further understanding how its expression is controlled at a local level, particularly in lieu of the involvement of inflammatory macrophages and obesity. Here, PRL is linked to obesity due to melanocortin 4 receptor deficiency.