In angiotensin II-induced hypertension models, the expansion of macrophages occurs mainly through two mechanisms: first, through the CCR2 pathway, which mediates the recruitment of circulating monocytes into local tissues where they differentiate into macrophages; second, through the self-proliferation of tissue-resident macrophages in the local microenvironment [8,36]. The gene discussed is CCR2; the disease is Hypertension.