Changes in serum and hepatic polyamine concentrations after 30%, 70% and 90% partial hepatectomy in rats

Polyamines have been reported to play an important role in stimulating hepatic regeneration after partial hepatectomy. To determine whether changes in systemic or hepatic polyamine concentrations correlate with the extent of the regenerative stimulus, serum and tissue putrescine, spermidine and spermine concentrations were determined in groups of adult male rats (n = 6 to 12/group) 0, 24, 48, and 72 hr after 30%, 70% or 90% partial hepatectomy. Serum putrescine levels were variably increased after partial hepatectomy and did not correlate with hepatic regenerative activity. Serum spermidine levels remained unaltered and spermine levels were undetectable both before and after partial hepatectomy. In hepatic tissue, only putrescine concentrations increased in proportion to the extent of hepatic resection. Moreover, there was a significant correlation between hepatic putrescine concentrations and restitution of liver mass (r = 0.778), DNA synthesis (r = 0.8026) and protein synthesis (r = 0.7034) (p less than 0.05). No significant correlations existed between hepatic spermidine or spermine concentrations and these parameters of hepatic regeneration. The results of this study support the hypothesis that hepatic putrescine plays an important role in stimulating hepatic regeneration after partial hepatectomy.