The ADRB2 also increases infiltration by pro-inflammatory macrophages, induces the production of IL-18, and sequentially stimulates the expression of connexin43 (Cx43) in fibroblasts in a paracrine manner, resulting in gap junction remodeling, myocardial fibrosis, and deterioration of cardiac function (31). Here, IL18 is linked to Myocardial fibrosis.