The Influence of Blood Glucose Change on Dopamine, Norepinephrine and Serotonin Concentration in the Frontal Lobe, Hippocampus and Striatum of Transient Ischemic Rat's Brain

Kim, Bong Ryong; Park, Jeong Youl; Park, Youn Kwan; Jung, Hung Sub; Lee, Ki Chan; Lee, Hoon Kab

Abstract

Hyperglycemia during either global or regional ischemia is widely known to be detrimental, and ischemia induced release of diverse neurotransmitters and the ensuing activation of specific postsynaptic receptors have been suggested to play a important role in the development of ischemic selective vulunerability. This study was undertaken to investigate the influence of blood glucose change on tissue concentration of some catecholamines ; dopamine, norepinephrine, serotonin, of the transient ischemic rat's brain, estimated by high performance liquid chromatography(HPLC) assay system, following transient bilateral forebrain ischemia in the rat's model subjected to 20 minutes of normothermic ischemia by two vesseles occulusion plus profound cortex, hippocampus and striatum respectively by HLPC. The concentrations of catecholamines were significantly decreased in all sampled areas in experimental groups compared with the control group(p<0.05), respectively(average decrease rate : norepinephrine 71%, dopamine 89%, serotonin 80% in frontal cortex ; norepinephrine 71%, dopamine 93%, serotonin 81% in hippocampus ; norepinephrine 33%, dopamine 35%, serotonin 78% in striatum). Dopamine was relatively decreased in concentration in frontal cortex and hippocampus, and serotonin was relatively decreased in striatum. But no statistic significancy(p>0.05) of catecholamines level between each experimental group(hyper-, hypo- and normoglycemic group) according to the change of blood sugar. The results suggested that blood glucose level did not influence the tissue concentration of dopamine, norepinephrine and serotonin in frontl cortex, hippocampus and striatum of transient ischemic rat's brain.