English H2 H2 H2 H2 (en) Histamine H2 receptor H2 H2 H2 H2 H2 H2 H2 Histamine H2 receptor Histamine H2 receptor H2 Histamine H2 receptor English H2 H2 H2 H2 H2 H2 H2 H2 H2 H2 H2 H2 H2 H2 H2 H2 English H2 H2 Histamine_H2_receptor. English H2