The role of nitric oxide in experimental cerulein induced pancreatitis.
An enhanced formation of nitric oxide (NO), due to the induction of inducible nitric oxide synthase (iNOS), has been implicated in the pathogenesis of shock and inflammation, but its role in acute pancreatitis still remains controversial. To clarify the role of NO in acute pancreatitis, the present experiment investigated the expression of iNOS and the effect of NOS inhibition on cerulein-induced pancreatitis in rats. Group I received intraperitoneal (ip) injection of normal saline. Group II received two ip injections of cerulein (20 microgram/kg). Group III received injections of N(G)-nitro-L-arginine methyl ester (L-NAME) (30 mg/kg) with cerulein. Group IV received L-arginine (250 mg/kg) with cerulein and L-NAME. The expression of iNOS in the pancreas was examined by western blot analysis. The plasma concentration of NO metabolites was measured. The severity of pancreatitis was assessed by measuring serum amylase, pancreas water content and histopathological examination. Compared with controls, the cerulein group displayed significantly increased expression of iNOS and raised plasma NO metabolites. Treatment with L-NAME significantly decreased hyperamylasemia, plasma NO level, and the extent of pancreatic injury. Treatment with L-arginine reversed the effects of L-NAME. These findings suggest that an enhanced formation of NO by iNOS plays an important role in the development of acute pancreatitis, and inhibition of NO production has the beneficial effects in reducing pancreas injury.
Um
Soon Ho
SH
Department of Internal Medicine, Institute of Digestive Disease and Nutrition, Korea University College of Medicine, Seoul, Korea.
Kwon
Yong Dae
YD
Kim
Chang Duck
CD
Lee
Hong Sik
HS
Jeen
Yoon Tae
YT
Chun
Hoon Jai
HJ
Lee
Sang Woo
SW
Choi
Jae Hyun
JH
Ryu
Ho Sang
HS
Hyun
Jin Hai
JH
D000681:Amylases / Q000097:blood; D000818:Animals; D001120:Arginine / Q000494:pharmacology; D015153:Blotting, Western; D002108:Ceruletide / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D007249:Inflammation; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009336:Necrosis; D009569:Nitric Oxide / Q000378:metabolism / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II; D010195:Pancreatitis / Q000139:chemically induced* / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D004791:Enzyme Inhibitors; D009569:Nitric Oxide; D002108:Ceruletide; D001120:Arginine; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat; D000681:Amylases; D019331:NG-Nitroarginine Methyl Ester