[Effects of early enteral feeding on nitric oxide synthase activity in small intestine in burned rat].

Objective: Our previous studies have proved that early enteral feeding could improve intestine blood flow after burn injury. But the mechanism was far from being clarified. This study was attempted to explore the effects of early enteral feeding on nitric oxide synthase (NOS) activity in burned rat small intestine and the relationship between the intestine mucosa blood flow (IMBF) and the activity of NOS.

Methods: The rats were randomly divided into three groups: burned control (B), burned and early enteral feeding (EF), and normal control (C). The activity of NOS including constitute NOS(cNOS) and inducible NOS(iNOS), and the IMBF were determined at postburn 0, 3, 6, 12, 24, 48 hours.

Results: It was found that cNOS activity and IMBF were decreased markedly postburn, and there was positive correlation between cNOS and IMBF (r = 0.97, P < 0.01). But the activity of iNOS, total NOS were increased significantly postburn, they had no correlation to the IMBF. In EF group cNOS activity and the IMBF were significantly higher, the iNOS was obviously lower than that of B group and there was no significant difference of total activity of NOS between two groups.

Conclusion: Our results suggested that NOS which is catalyzed from cNOS may play main role in adjusting IMBF. By using early enteral feeding the activity of cNOS is increased and the ischemic state in small intestine is improved after burn injury.