Liposomes are useful
drug carriers. In this study,
adenosine triphosphate (
ATP) was entrapped in
liposomes (Lip-
ATP). Anesthetized rats were given Lip-
ATP (5 mg/kg as
ATP), free
ATP (5 mg/kg) or saline (control group) during stabilization. Then, the rats were exposed to 30 min of
hypovolemic shock and 30 min of reperfusion. Administration of Lip-
ATP significantly improved hepatic blood flow during
shock (13.2 +/- 1.7 ml/min/100 g tissue in the Lip-
ATP group vs. 9.4 +/- 2.2, in the control group, and 8.9 +/- 2.9 in the free
ATP group) and during reperfusion (20.9 +/- 2.3, 16.3 +/- 2.2, and 16.2 +/- 1.8 ml/min/100 g tissue, respectively). The serum levels of hepatic
enzymes (ALT, AST and LDH) were significantly lower in the Lip-
ATP group after reperfusion when compared with the control and free
ATP groups. Administration of Lip-
ATP also produced the best recovery of hepatic
ATP level. These findings indicate that Lip-
ATP increased hepatic blood flow during
shock and reperfusion, presumably by improving the energy charge and metabolism of the hepatocytes. Thus, Lip-
ATP appears to be a useful agent for liver injury induced by
hypovolemic shock.