Extrahepatic complications to cirrhosis and portal hypertension: Haemodynamic and homeostatic aspects

Figure 4 Mechanisms of cirrhotic cardiomyopathy. The figure reviews the most important mechanisms involved in cirrhotic cardiomyopathy: Desensitisation and downregulation of β-adrenergic receptors with decreased content of G-protein (Gαi: inhibitory G protein; Gαs: stimulatory G protein) and following impaired intracellular signalling; alterations in particular in M2 muscarinic receptors; upregulation of cannabinoid 1-receptor stimulation; altered plasma membrane cholesterol/phospholipid ratio; increased inhibitory effects of haemooxygenase (HO), carbon monoxide (CO), nitric oxide (NO), and tumour necrosis factor-α (TNF-α); reduced density of potassium channels; changed function and fluxes through L-type calcium channels; altered ratio and function of collagens and titins. Many post-receptor effects are mediated by adenylcyclase (AC) inhibition or stimulation. PKA: Protein kinase A.