Kcnj2, Kcnj12 and Atp2a2 (Serca2) are down-regulated whereas Ryr2, Casq2 and Camk2a display no significant differences (Fig 2) and only Pln is up-regulated in HTN left atrial chambers as compared to control normotensive rats (Fig 2). The gene discussed is CASQ2; the disease is hypertensive disorder.