PCSK9 and hyperlipidemia: Also consistent with impaired NO production, which is known to promote atherosclerosis (24, 25), Atgl ECKO mice were predisposed to atherosclerosis in the AAV8-PCSK9 (proprotein convertase subtilisin/kexin type 9) model (Figure 3, A and B), despite equivalent reduction in liver expression of LDLR protein (Figure 3C) and hyperlipidemia (Figure 3, D–F) as in control mice.