Objectives Cerebral vasospasm after subarachnoid haemorrhage (SAH) is associated with cerebrovascular contractile receptor upregulation resulted from haemolysis in the subarachnoid space. This study developed a new magnesium-rich artificial cerebrospinal fluid (MACSF) formula and investigated its effects on receptor-mediated contraction in rat basilar arteries. Methods Clear and haemorrhagic cerebrospinal fluid (CSF) were collected from patients with hydrocephalus or SAH. MACSF was freshly prepared using clinical intravenous injections. Rat basilar arteries were segmented and incubated with clear CSF, haemorrhagic CSF or MACSF. The contractile responses were studied by myograph. The messenger ribonucleic acid (mRNA) and protein expression of 5-hydroxytryptamine 1B (5-HT1B), endothelin subtype B (ETB) and endothelin subtype A (ETA) receptors were evaluated by real-time polymerase chain reaction (PCR) and Western blot analyses. Results Haemorrhagic CSF exposure shifted the contractile curves induced by 5-hydroxytryptamine (5-HT), sarafotoxins 6c (S6c) and endothelin-1 (ET-1) leftward with increased maximal contraction values. Furthermore, mRNA and protein expression were markedly elevated for 5-HT1B, ETB and ETA receptors on arteries exposed to haemorrhagic CSF. However, the contractile responses to 5-HT, S6c or ET-1 and expression of 5-HT1B, ETB and ETA receptors in rat cerebral arteries exposed to MACSF remained unaffected compared to those exposed to clear CSF. Besides, unlike normal saline which can inactive in-vitro vessels, MACSF can maintain their physiological activity. Conclusion Haemorrhagic CSF induces upregulation of 5-HT1B, ETB and ETA receptors in rat cerebral arteries. However, MACSF can maintain in-vitro rat basilar arteries in good physiological activity and normal expression of contractile 5-HT and ET receptors.

中文翻译：

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新型富含镁的人工脑脊髓液对大鼠脑动脉收缩性5-羟色胺和内皮素受体的影响。

目的蛛网膜下腔出血（SAH）后的脑血管痉挛与蛛网膜下腔出血引起的脑血管收缩受体上调有关。这项研究开发了一种新的富含镁的人工脑脊髓液（MACSF）配方，并研究了其对大鼠基底动脉受体介导的收缩的影响。方法收集脑积水或SAH患者的清净和出血性脑脊液（CSF）。MACSF是使用临床静脉注射新鲜制备的。将大鼠基底动脉切开并与透明CSF，出血CSF或MACSF一起孵育。收缩反应通过肌电图检查。信使核糖核酸（mRNA）和5-羟色胺1B（5-HT1B）的蛋白质表达，通过实时聚合酶链反应（PCR）和Western印迹分析评估了B型内皮素（ETB）和A型内皮素（ETA）受体。结果出血性脑脊液暴露使5-羟色胺（5-HT），sarafotoxins 6c（S6c）和内皮素-1（ET-1）诱导的收缩曲线向左移动，最大收缩值增加。此外，暴露于出血性CSF的动脉中5-HT1B，ETB和ETA受体的mRNA和蛋白表达显着升高。然而，与暴露于透明CSF的大鼠相比，暴露于MACSF的大鼠脑动脉对5-HT，S6c或ET-1的收缩反应以及5-HT1B，ETB和ETA受体的表达未受影响。此外，与可以使体外血管失活的生理盐水不同，MACSF可以维持其生理活性。结论出血性脑脊液可诱导大鼠脑动脉5-HT1B，ETB和ETA受体上调。但是，MACSF可以维持体外大鼠基底动脉良好的生理活性以及可收缩的5-HT和ET受体的正常表达。