大鼠脑损伤后脑与血清中5-羟色胺和5-羟吲哚醋酸改变及赛庚啶的作用——荧光分光检测与免疫组化研究

Effect of cyproheptadium on changes of 5-HT and 5-HIAA in rat brain cortex and serum following brain injury:an experimental study with spectrofluorometer and immunocytochemistry

本实验选用 Wistar 大鼠100只,用荧光分光仪检测大鼠脑落体伤后不同时间脑皮质和血清中5-羟色胺(5-HT)及其代谢产物5-羟吲哚醋酸(5-HIAA)含量。并采用免疫组化(ABC)法研究脑干中缝核群5-HT 能神经元中5-HT 合成及释放过程。同时,选择5-HT 受体阻断剂赛庚啶治疗,观察其对5-HT 及5-HIAA 变化的影响。结果:脑损伤后脑皮质中5-HT 和5-HIAA 含量均明显升高。伤后6小时,5HT 含量上升为1.99±0.35(μg/g),5-HIAA 上升为2.84±0.75(μg/g),分别是对照值的2.2和3倍;伤后24～48小时达高峰。血清中5-HT 变化不明显;而5-HIAA 含量亦有较明显升高。免疫组化研究发现,脑损伤后6～24小时,5-HT 能神经元中5-HT 合成变化不明显,而脑微血管壁中5-HT 明显增加,伴随脑水肿加剧。应用赛庚啶治疗后,脑皮质中5-HT 和5-HIAA 含量降低较明显,分别为1.32±0.09μg/g 及1.36±0.10μg/g;免疫组化观察见脑微血管壁中5-HT 明显减少,脑水肿有所减轻。

The changes of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) levels in the brain cortex and serumwere studied with spectrofluorometer follow-ing brain injury in 100 rats.The synthesis andrelease of 5-HT within neurons in the rapheregion of medullae oblongatae were investigat-ed by immunocytochemistry (ABC) method. The blocker of 5-HT receptor-cyproheptadi-um,was selected to show its effect on alter-ations of 5-HT and 5-HIAA in this experi-ment.The results showed that the levels of 5-HT and 5-HIAA in the brain cortex increasedremarkably after brain injury.The values of5-HT and 5-HIAA in the brain cortex were1.994-0.35 and 2.84±0.75 (μg/g) 6 hoursafter brain injury,and reached their peaks at24～48 hours after injury.The increase of 5-HT in the serum was not significant,but thelevel of 5-HIAA in the serum increases evi-dently.The immunocytochemistry examiningshowed that the synthesis of 5-HT within neu-rons of raphe region was slightly increased at6～24 hours after brain injury.At the sametime,5-HT in the wall of cerebral microvesselwas increased markedly,and revealed severecerebral edema.After cyproheptadium treat-ment the levels of 5-HT and 5-HIAA reducedmarkedly,and the cerebral edema decreasedslightly.