Difference In SAA Activity Between Unstimulated And Stimulated Saliva Among Patience With Pi-deficiency And Healthy People And Its Mechanism

Objective: To compare the difference of s AA activity between unstimulated and stimulated saliva from patient with pi-deficiency and healthy adult, and to detect the secretion mechanism inducing the difference. In order to explain the molecule mechanism of “spleen controlling saliva” and built up other indicators of diagnosingMethods: 1.Clinical experiment: 30 patients with pi-deficiency and 30 healthy adults were recruited to collect their saliva of before and after stimulated by citric acid within a period time. Then the saliva flow rate, p H, the total protein, s AA activity, s AA amount, AMY1 copy number were determined.(1) Indicators of saliva sample were compared between patients with pi-deficiency and healthy adults of unstimulated or stimulated, and between unstimulated and stimulated within each group.(2) The correlation among s AA amount, AMY1 copy number and s AA activity were assessed. 2.Animal experiment:(1) 30 female SD rats were chosen to built a saliva collected method of before and after stimulated by citric acid.(2) 48 female SD rats were selected and raised in SPF environment in addition. The rats were divided into two groups, the model group(n=24) and the control group(n=24). The model group was received reserpine to build pideficiency model. Unstimulated and stimulated saliva were collected and s AA activity was determined.(3) The model group was divided into 3 groups, naming as the pi-deficiency control group, the pi-deficiency-agonist group, the pi-deficiency-blocker group. The control group was divided into 3 groups, naming as the normal control group, the normal-agonist group, the normal-blocker group. Unstimulated and stimulated saliva were collected and s AA activity was determined. Then rats were dissected and parotid glands were obtained. s AA activity, s AA amount, c AMP amount, β-AR protein expression were determined. ① Difference between unstimulated and stimulated saliva in both groups were compared, between the pi-deficiency group and the control group of unstimulated or stimulated saliva in addition. ②Difference of all indicators of parotid gland between the pi-deficiency group and the normal group were compared. ③ Influence of β-AR agonist and block to both groups were observed.Result: 1.Clinical experiment:(1) ① In unstimulated saliva, no significant differences were found between two groups, except in p H value, patients with pi-deficiency showed significant higher than healthy adults. In stimulated saliva, patients with pi-deficiency showed significant lower in saliva flow rate, the total protein amount, s AA activity and s AA amount than healthy adults except in p H value. There was no difference in AMY1 copy number between two group. ②Between unstimulated and stimulated saliva, no significant difference were showed in patients with pi-deficiency. And all indicators of stimulated/ unstimulated ratios were a slightly larger than 1, except the total protein amount, which was smaller than 1. While in healthy adult, there were significant differences in all indicators. And theirs stimulated/ unstimulated ratios were lager than 1. Only s AA activity ratio between two groups showed significant difference.(2) The role played by s AA amount and AMY1 copy number to s AA activity were analyzed. The results showed significant positive correlation among s AA amount and s AA activity(healthy adults: unstimulated r=0.61, stimulated r=0.67; patients with pi-deficiency: unstimulated r=0.69, stimulated r=0.72). It showed significant correlation among AMY1 copy number and s AA activity in unstimulated saliva(healthy adults: r=0.52, patients with pideficiency: r=0.51), while no correlation in stimulated saliva. In addition, the correlation between s AA activity ratio and s AA amount ratio were significant(healthy adults: r=0.85, patients with pi-deficiency: r=0.36). There were significant correlation among s AA activity ratio and AMY1 copy number in patients with pi-deficiency(r=0.45), while no correlation in healthy adults. 2.Animal experiment:(1) The result of saliva collection method showed stimulated saliva collected by putting 0.4mol/L 0.50×0.50 cm of citric acid filter paper at the tongue tip 30 s every 2.5min in 15 min was the best, s AA activity and saliva flow rate increase significantly. The correlation of unstimulated saliva among s AA activity and flow rate was positive significantly, while the correlation of stimulation was negative significantly.(2) The pi-deficiency group lost significantly in weight compared with the control group during 11 days, along with significant pi-deficiency signs of ptosis, getting together, humpback, no luster in fur, semiliquid stool.(3) ① Unstimulated and stimulated saliva sample showed no difference from the pideficiency group, while significant increase from the control group. There was no difference of unstimulated saliva between two groups while significant of stimulated saliva. ② Parotid gland indicators testing from the pi-deficiency group showed significant higher in s AA activity and s AA amount, lower in β1-AR protein expression, higher in β2-AR protein expression, lower in c AMP amount than from the normal group. ③ After being interfered by agonist in both group, s AA activity increased in saliva sample, s AA activity decreased significantly in parotid gland. While indicators showed no difference after being interfered by blocker.Conclusion: Patients with pi-deficiency revealed insensitivity to acid, which caused decrease of s AA activity ratio. It revealed reasons that the decline of s AA activity in patients with pi-deficiency was relative to s AA amount and had a genetic basis. Rats in the pideficiency group with receptor expression barriers induced secretion pathway disorder. It explained patients with pi-deficiency had depressed acute response function.