Quantitative determination of endogenous nitric oxide in the mouse skin in vivo by microdialysis.

We have developed a subcutaneous microdialysis system for the determination of nitric oxide (NO) concentration in the skin. The skin was microdialyzed using a degassed solution containing 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl 3-oxide and the perfusate was reacted on-line with Griess' reagent. This method could reveal NO production following intradermal injection of bradykinin (10-100 nmol/site) in mice. The increase in cutaneous NO after bradykinin (100 nmol/site) was dose dependently suppressed by the NO synthase inhibitor. NG-nitro-L-arginine methyl ester, and the bradykinin B, receptor antagonist, D-Arg-[Hyp3, Thi5.8, D-Phe7]-bradykinin. This system may be useful for pharmacological and physiological experiments on the role of NO in the skin.