The rat learning and memory impairment induced by chronic alcoholism and expression of hippocampus p-CREB

Objective Through establishing the rat model of learning and memory disorder,This study is to detect the relative densities of p-CREB distribution and expression in hippocampus,and explore the effects of p-CREB on learning and memory disorder of rat chronic alcoholism. Methods 60 adult male SD rats were randomly divided to 4 groups:control group,low alcohol administration group(LAA group),moderate alcohol administration group(MAA group),high alcohol administration group(HAA group). Control group were administrated by normal saline,different dosage of 55% alcohol (5 ml·kg-1·d-1,10 ml·kg-1·d-1 and 15 ml·kg-1·d-1) were respectively administrated to LAA,MAA and HAA group. Morris water maze was used to detect the changes of learning and memory. Distribution and expression of p-CREB in hippocampus CA1,CA3 region and dentate gyrus were observed with immunohistochemical SABC staining. The p-CREB-immunoreactive cells numbers in hippocampal formation were detected by Olympus microscope and image analysis system. Results The impairment of learning and memory was unequal.The p-CREB-immunoreactive cells in control group hippocampus were distributed more than in LAA group,MAA group and HAA group hippocampus,and the colour of p-CREB-immunoreactive cells was deeper in CA1 and CA3 region,but p-CREB-immunoreactive cells were not observed in dentate gyrus.The numbers of p-CREB-immunoreactive cells in CA1,CA3 region of LAA group,MAA group and HAA group decreased obviously after alcohol intragastric administration [CA1:85.45±4.32,74.42±8.94,73.56±7.64; CA3:245.29±15.36,206.90±15.37,201.96±11.37] compared with control group [CA1:90.54± 6.38; CA3:273.79±16.87 ]( P <0.05). Conclusion After 6 weeks' high ethanol administration,the impairments of learning and memory were unequal,the expression of p-CREB was observed in all groups,but there are some differences.These suggest that p-CREB might play an important role in the rat learning and memory disorder induced by chronic alcoholism. Key words: Alcoholism; Hippocampus; Learning and memory; p-CREB