Detection of Nitric Oxide Generation by Electron Spin Resonance Spectroscopy after Partial Hepatectomy

抄録

Nitric oxide (NO _??_), a paramagnetic molecule, has a very short half-life of less than five seconds. The direct measurement of NO _??_ is therefore difficult and is not commonly performed. The liver is one of the organs in the body that is clearly influenced by NO _??_ which is generated in response to septic shock, portal hypertension and liver surgery such as, in the case presented here, partial hepatectomy. To detect time-dependent changes in NO _??_ after hepatectomy and regeneration of the liver, we used ex vivo electron spin resonance (ESR) spectroscopy by injection of an N-methyl-D-glucamine dithiocarbamate (MGD) and Fe²⁺ complex ( [ (MGD) ₂Fe] ) . After injection of this complex, NO _??_ signals were detected by ESR in both regenerating and sham-operated livers. NO _??_ generation had increased significantly at 36 h and peaked at 72 h after partial hepatectomy. The expression of inducible nitric oxide (iNOS) mRNA was analyzed by real-time PCR and its maximum level was detected at 72 h after partial hepatectomy. These results indicate that NO _??_ may play an important role in regulating liver regeneration after partial hepatectomy.