[Relationship between plasma carbon monoxide and blood-brain barrier permeability in cirrhotic rats].

OBJECTIVE

To explore the relationship between plasma levels of carbon monoxide and blood-brain permeability in cirrhotic rats.

METHODS

We measured mean arterial pressure (MAP), heart rate, plasma levels of carbon monoxide and amount of Evans blue in the brain tissue taken as the index of blood-brain permeability in cirrhotic rats (n=10) and controls (n=10).

RESULTS

Cirrhotic rats showed significant increases in plasma carbon monoxide and amount of Evans blue in brain tissue compared with controls [(18.37 +/- 1.79) micromol/L,(18.52 +.- 1.39) ng/mg vs (10.27 +/- 1.21) micromol/L, (15.08 +/- 1.06) ng/mg; P< 0.01]. Carbon monoxide levels in cirrhotic rats correlated positively with blood-brain barrier permeability and inversely with MAP (r=0.72, P< 0.01; r= -0.67, P< 0.05).

CONCLUSIONS

Carbon monoxide, involving in the occurrence of hypotension and the increase of blood-brain barrier permeability, may play a role in the development of hepatic encephalopathy.