Substance P,vasoactive intestinal peptide,and leu-enkephalin in plasma and gastric juice of patients with precancerous lesions and gastric cancer

AIM: To investigate the changes of the brain-gut-peptide concentrations in the plasma and gastric juice and their relations to gastric diseases.METHODS: A total of 83 subjects were part of the study. Of those, 28 had chronic atrophic gastritis with precancerous lesions, 22 had gastric cancer in an advanced stage, and 33 were healthy subjects for a control group. Samples of fasting blood and gastric juice were collected. Levels of substance P (SP), vasoactive intestinal peptide (VIP) and leu-enkephalin (LEK) in plasma and gastric juice were measured with radioimmunoassay kits expressed as ng/L.RESULTS: In patients with gastric cancer, the SP levels (83.7 ± 11.0 vs 39.6 ± 4.5, P < 0.01; 24.0 ± 1.6 vs 17.8 ± 1.5, P < 0.05) and LEK in plasma and gastric juice (226.2 ± 15.4 vs 180.3 ± 13.1, P < 0.01; 55.0 ± 3.4 vs 30.7 ± 2.4, P < 0.05), and VIP of gastric juice (80.5 ± 2.9 vs 64.3 ± 4.1, P < 0.05) were higher than those in the controls. The SP and LEK levels of plasma correlated with those of gastric juice (r = 0.432 and 0.516, P < 0.05). In the post-surgical gastric cancer, plasma levels of SP and gastric juice LEK were lower than the pre-surgical levels (P < 0.05). In the precancerous lesions, plasma and gastric juice LEK levels and gastric juice VIP levels were increased (P < 0.05), and the plasma LEK level correlated with the gastric juice LEK level (r = 0.398, P < 0.05).CONCLUSION: Measurement of concentrations of SP, VIP, and LEK in plasma and gastric juice is of clinical significance in detecting certain stomach diseases.