CNR1 and obesity due to melanocortin 4 receptor deficiency: CB1 activity in adipose tissue is also associated with ovarian dysfunction in polycystic ovary syndrome (PCOS).138 CB1 activity (but not CB2) is significantly elevated in adipose tissue of patients with PCOS.138 Notably, they also found that this increase correlated with insulin resistance.138 Insulin resistance and obesity are key drivers of PCOS, thus increased ECS signaling may represent a link between these conditions in female patients.