해마 절편에서 저산소증에 의한 5-Hydroxytryptamine 유리변동에 미치는 Glucose의 역할 = The Relationship of Glucose Deprivation and Hypoxia on the Release of 5-Hydorxytryptamine from Rat Hippocampal Slices

다국어 초록 (Multilingual Abstract)

During cerebral ischemia two factors, hypoxia and reduction of glucose concentration can act a modulating stressor affecting the release of amine neurotransmitters including 5-hydroxytryptamine(5-HT). This study performed to investigate the relationship between the effects of glucose deprivation and the hypoxia on the spontaneous ＾3H-5-HT release from the rat hippocampal slices.
Environmental group were divided into 4 groups for this study : normoxic. Normoglycemic (10mM) group ; hypoxic group ; glucose deprivated group(10mM) ; and hypoxic, glucose deprived group.
The hippocampus was obtained from the rat brain and sliced 400㎛ thickness with manual chopper. After 30min:s preincubation in the normal buffer, the slices were incubated for 20min in a buffer containing ＾3H-5-HT(0.1μM, 74μCi) for uptake and washed. To measure the release of ＾3H-5-HT into the buffer, the incubation medium was brained off and refilled every ten minutes through a sequence of 14 tubes. Induction of hypoxia (gassing it with 95% N_2/5% CO_2) and/or glucose deprivation was done in the 6th and 7th tube. The radioactivities in each buffer and the tissue were counted using scintillation counter and t도 results were expressed as a percentage of the total radioactivity.
When slices were exposed to hypoxia for 20min, ＾3H-5-HT release was decreased and a rebound release of ＾3H-5-HT was observed on the post-hypoxic peroid. In hypoxic glucose deprived group. the release of ＾3H-5-HT was markedly increased. So the pattern of ＾3H-5-HT release was opposite to the hypoxic group.
These results suggested that hypoxic insult itself causes inhibitory neuronal response during hypoxic perioid, but additional glucose deprivation converts the inhibitory hypoxic response to neuronal excitation.