FK506 with portal decompression exerts beneficial effects following extended hepatectomy in dogs

The present study was designed to elucidate the effectiveness of portal dec ompression and FK506 (FK) pretreatment in extended hepatectomy in dogs. In the first set of experiment the effect of portal decompression was evaluate d in two groups of dogs which underwent extended hepatectomies (80%) with o r without (control) a side-to-side portacaval shunt. The presence of the sh unt significantly (p < 0.05) improved the 7-day survival of the animals (57 .1%) when compared with those of the control group (28.6%) and eventually t he portal pressure was significantly lower and mean arterial pressure was s ignificantly higher in the shunt group (p < 0.05). Moreover, the animals wi th lower portal pressure (less than or equal to 220 mm of saline) had a sig nificantly improved 7-day survival rate than those with higher portal press ure (p < 0.001). To evaluate the role of FK pretreatment in extended hepate ctomy, a more severe model of 90% hepatectomy was used in four different gr oups: portacaval shunt, shunt and FK pretreatment, FK pretreatment, and hep atectomy only (control). Although the shunt improved the survival rate in t he 80% hepatectomy model, neither shunt (8.3%) nor FK pretreatment (0%) ind ependently improved the survival of the animals when the hepatectomy was ex tended to 90%. FK pretreatment significantly improved the survival (33.3%, p < 0.05) and hepatic functions of the animals only in the presence of a sh unt. Also hepatic microcirculation measured with a laser Doppler flowmeter was significantly better in the remnant liver of all treated groups than in the control group (p < 0.01). In conclusion, extended hepatectomy (90%) co uld be performed in otherwise normal liver after FK pretreatment and a side -to-side portacaval shunt, which improve the regenerative response in a sta ble hemodynamic animal.