Our study investigates the impact of different volume sham control and excitotoxin microinfusions in vivo on local reactive astroglial response within rat nucleus basalis (NB). We followed the effects of unilateral 200, 100, and 50 nL of sham-control (phosphate buffer PBS) versus ibotenic acid (IBO) microinfusions, mechanical NB lesion (10 µL Hamylton syringe needle positioned into NB for 5 min), or physiological control (intact brain), on the local reactive astroglial response within the NB site, by immunoreactivity against glial fibrillary acidic protein (GFAP). NB lesions were identified by NADPHdiaphorase histochemistry. Local astrocytes responses within NB were suppressed by both high volume microinfusions, PBS and IBO (200 and 100 nL) versus mechanical lesion. Our study has proved, for the first time, the volume of microinfusion as critical for any selective pharmacological stimulation or lesion in vivo, and suggest the microinfusion volume less than 50nL as protective for physiological astroglial reactivity.

中文翻译：

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高剂量的微输注抑制大鼠基底核内的局部星形胶质细胞反应。

我们的研究调查了体内不同体积的假手术控制和兴奋毒素微输注对大鼠基底核（NB）内局部反应性星形胶质反应的影响。我们观察了单侧200、100和50 nL的假对照（磷酸盐缓冲液PBS）与异丁酸（IBO）微输注，机械性NB病变（将10 µL Hamylton注射器针头置于NB中5分钟）或生理对照的影响。 （完整的大脑），通过针对神经胶质纤维酸性蛋白（GFAP）的免疫反应性，在NB部位内发生局部反应性星形胶质反应。通过NADPH心肌黄酶组织化学鉴定NB病变。相对于机械损伤，高剂量微量输注，PBS和IBO（200和100 nL）抑制了NB内部的局部星形胶质细胞反应。我们的研究首次证明了