HSPA1A and essential hypertension: HSP70 expression at protein level by indirect ELISA method in 132 patients with essential hypertension (0.31 ± 0.03 RLU) and 132 healthy control groups (0.18 ± 0.02 RLU) (P < 0.0001) and the protein level was found to be 1.7 times higher in patients as compared to that of controls (Fig 2B).