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Through the establishment of various degrees of chronic intermittent hypoxia in the rat model, analog severe obstructive sleep apnea hypopnea syndrome intermittent hypoxia pathophysiologic characteristics of varying degrees of chronic intermittent hypoxia on memory function in rats and JNK protein impact. Methods adult male Wistar rats of 144 (body weight 170 ± 10 g) were randomly divided into 3 groups: control group (UC), 5% of the chronic intermittent hypoxia group (5% CIH group) and 10% of chronic intermittent low oxygen group (10% CIH group), the UC group normal feeding the CIH rats exposed 8 hours daily into the homemade hypoxia cabin, exposed to 2, 4, 6, 8 w Morris water maze test, rats were detected learning and memory function, chemical colorimetric assay the hippocampal tissue superoxide dismutase (SOD) activity and malondialdehyde (MDA) levels, immunohistochemistry method chemical JNK protein expression detected by Western blot. Statistical analysis using SPSS13.0 statistical software to analyze data, all measurement data are expressed as mean ± standard deviation ((x | -) ± s) said, using one-way ANOVA, pairwise comparisons using the Least significant difference (LSD) method, P lt; 0.05 was considered statistically significant. Results 1 Morris water maze results: the same group at different time points: intermittent hypoxic rats with hypoxia time extend longer escape latency across the targeted phenomenon time. 10% CIH group 2w, 4w, 6w between more significant (P lt; 0.05), between 5% CIH group 2w, 4w, 6w, 8w were statistically significant (P lt; 0.05); different group of the same point in time: comparing with the UC group, 10% CIH rats start from 4w 5% CIH group from 2w longer escape latency across the target quadrant time, both groups in the first 6w obvious. Compared with 10% CIH group, 5% CIH rats 2w, 4w, 6w, 8w escape latency was significantly prolonged across the target quadrant significantly shortened, were statistically significant (P lt; 0.05). Extension of time with hypoxia, CIH rat hippocampal tissue SOD activity decreased MDA content expression increases, the difference was significant (P lt; 0.05) at each time point, pairwise comparisons between the three groups, significant differences statistically significant (P lt; 0.05). 3 phosphorylation of JNK (p-JNK) protein immunohistochemistry results: observed under an optical microscope most positive expression of cell nucleus brownish yellow or pale yellow, the rats in each group were positive expressing cells, mainly in the hippocampal CAl . Different time points within the same group of comparison: 10% CIH, 5% of the CIH group of rats with hypoxia time extension of an increase in p-JNK protein expression in hippocampal CA1 region, 6w integrated optical density (IOD) value, 6w, 8w ' comparisons not statistically significant (P gt; 0.05); among the groups at the same time point comparison: comparing with the UC group, hypoxia group 2w, 4w, 6w, 8w hippocampal CA1 region p-JNK protein expression increased (P lt; 0.05), compared with 10% CIH group, 5% CIH group 2w, 4w, 6w, 8w hippocampal CA1 region of p-JNK protein expression increased, and the difference was statistically significant (P lt; 0.05). 4 p-JNK protein Western blot results: within the same group in a different point in time: the CIH rats with hypoxia extend p-JNK protein expression was increased; among the groups at the same time point comparison: comparing with the UC group, CIH Group significant differences was statistically significant (P lt; 0.05), and 5% of the CIH and 10% CIH significant difference between statistical significance (P lt; 0.05). Conclusions Chronic intermittent hypoxia can cause dysfunction of learning and memory in rats, and aggravated the injury is more pronounced with low oxygen levels, severe hypoxia early manifestation of memory dysfunction. Aggravated with low oxygen levels, intermittent hypoxic rats hippocampal tissue SOD activity decreased increased MDA content expression. Chronic intermittent hypoxia rats p-JNK protein expression of hippocampal neurons are mainly located in the nucleus, maximum expression in the hippocampal CA1 region, and with hypoxia severity, p-JNK protein expression. 4 chronic intermittent hypoxia causes dysfunction of learning and memory in rats may cause oxidative stress and hypoxia, activation of the JNK pathway, caused by increased expression of p-JNK.
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