EFFECT OF ORTHOTOPIC TRANSPLANTATION AND CHEMICAL DENERVATION OF THE LIVER ON HEPATIC HEMODYNAMICS IN THE RAT

The involvement of the sympathetic nervous system in the control of ba sal hepatic hemodynamics was investigated. Hepatic denervation was ach ieved by orthotopic transplantation or chemical denervation of the org an. In male Lewis rats, transplantation with rearterialization of the graft was performed. Chemical denervation was achieved by intraportal injection of 6-hydroxydopamine (75 mg/kg). Normal liver physiology was confirmed by histology and liver function tests. Four weeks post-tran splantation and 7 days post-denervation, histological examination reve aled no differences between transplanted, denervated and untreated or sham-operated control animals. Liver function measured by standard tes ts (e.g., plasma SGOT, bilirubin) was normal in all groups. The rate c onstants for aminopyrine breakdown in transplanted (0.015 +/- 0.005 mi n(-1)), denervated (0.015 +/- 0.0012 min(-1)) and control rats (0.015 +/- 0.001 min(-1)) were not significantly different. No significant di fference in the rate of galactose breakdown was found. Total liver blo od flow (measured by the Xe-133 clearance technique in the anesthetize d animal) was unaffected by transplantation (rate constant, 0.245 +/- 0.062 min(-1); control 0.279 +/- 0.011 min(-1)). The interlobular dist ribution of portal blood flow was tested by intraportal injection of C r-51-labelled microspheres. A linear relationship between flow to lobe and lobe size was confirmed in control (r = 0.95), denervated, (r = 0 .99) and transplanted rats (r = 0.97) and the 'relative' flow to each lobe was not significantly different in the 3 groups. No significant d ifferences in the 'core' to 'periphery' distribution of portal blood f low were found in the 3 groups. A small but significant portal systemi c shunt was found in transplanted but not denervated or control animal s. We conclude that basal hepatic hemodynamics are probably not under sympathetic control.