ABSTRACT
AIM:To study the changes in lymphatic motion and histochemical stain of nitric oxide synthase(NOS) in the early phase of acute rat endotoxemia and explore their relationship. METHODS: After lipopolysaccharide (LPS) was injected into femoral vein, rats' mesenteric lymphatic were inspected within two hours. Paraffin section was stained by HE, frozen section by NADPH diaphorase histochemistry. RESULTS: In LPS group, the mesenteric lymphatic diameter was greater than that in the control and contractile frequency was decreased, the villi central lacteal and submucosal microlymphatics of small intestine was extremely dilated under microscope. In LPS and control group, NOS was positive in lymphatic endothelia and the nerve fibers in the vessels' wall. CONCLUSION: In the early stage of acute endotoxemia, the lymphatic vessles dilated and contractile activity diminished, NOS may play an important role in these changes.