TMBIM4 and pulmonary arterial hypertension: The protein and RNA levels of NRF 2 were measurably rescued by S1R activation in the P + F group (Figure 5a, 5e, 5h) Similarly, HO 1 expression was downgraded dramatically in the PAH group (Figure 5a,5f,5i) but partly recovered in response to fluvoxamine in the P + F group (Figure 5a,5f,5i) (Figure 5).