本文選題：術(shù)后認(rèn)知功能障礙 + 中樞膽堿能神經(jīng)　； 參考：《上海交通大學(xué)》2014年博士論文

【摘要】：背景 術(shù)后認(rèn)知功能障礙（POCD）是患者麻醉手術(shù)后出現(xiàn)的記憶力下降、注意力不能集中等認(rèn)知功能改變，嚴(yán)重影響患者生活質(zhì)量，增加術(shù)后死亡率。然而POCD的發(fā)病機(jī)制仍然不明。雖然老齡是目前POCD唯一明確的誘發(fā)因素，但增齡導(dǎo)致POCD發(fā)病增加的原因還不清楚。中樞膽堿能神經(jīng)系統(tǒng)在學(xué)習(xí)、記憶等認(rèn)知功能方面起著重要調(diào)節(jié)作用，而且中樞膽堿能系統(tǒng)隨著年齡增長的退化可以造成其對抗中樞傷害性反應(yīng)的能力下降。因此，本課題擬證明中樞膽堿能系統(tǒng)的退化是造成老年動物術(shù)后認(rèn)知功能損傷的主要原因，并探討其具體機(jī)制與神經(jīng)生長因子（NGF）的關(guān)系，為POCD的防治提供新的思路。 快速老化模型小鼠（SAM）是一種近交系衰老模型鼠，其中SAMP-8品系是目前用于研究阿爾茨海默病（AD）早期神經(jīng)退行性病變較理想的模型。本課題擬評估SAMP-8小鼠作為非轉(zhuǎn)基因AD動物模型對吸入麻醉藥的敏感性變化，為臨床AD患者優(yōu)化麻醉用藥提供參考。 方法與結(jié)果 1、中樞膽堿能神經(jīng)退化在手術(shù)造成老年小鼠POCD中的作用 方法：實(shí)驗(yàn)一：選取2月齡、18月齡C57BL/6小鼠行闌尾切除術(shù)，術(shù)后第3天應(yīng)用Morris水迷宮試驗(yàn)測試小鼠空間學(xué)習(xí)和記憶能力的改變，水迷宮結(jié)束后采用Western Blot和生物化學(xué)發(fā)光技術(shù)檢測小鼠海馬膽堿能神經(jīng)主要標(biāo)志物的表達(dá)變化，包括乙酰膽堿轉(zhuǎn)移酶（ChAT）、乙酰膽堿酯酶（AChE）、囊泡乙酰膽堿轉(zhuǎn)運(yùn)體（VAChT）、膽堿轉(zhuǎn)運(yùn)體（CHT）以及海馬乙酰膽堿（ACh）的含量；實(shí)驗(yàn)二：為驗(yàn)證中樞膽堿能系統(tǒng)在手術(shù)引起老年小鼠學(xué)習(xí)記憶減退中的作用，給予老年小鼠5mg/kg/day多奈哌齊連續(xù)灌胃4周，提高中樞膽堿能神經(jīng)的活性，灌胃結(jié)束后第1天行闌尾切除術(shù)，術(shù)后第3天水迷宮試驗(yàn)測試小鼠空間學(xué)習(xí)和記憶能力的改變，水迷宮結(jié)束后采用Western Blot和生物化學(xué)發(fā)光技術(shù)檢測海馬膽堿能神經(jīng)主要標(biāo)志物的蛋白表達(dá)和ACh含量的變化；實(shí)驗(yàn)三：為進(jìn)一步證明中樞膽堿能系統(tǒng)的退化是手術(shù)引起小鼠學(xué)習(xí)記憶減退的重要原因，給予成年小鼠側(cè)腦室內(nèi)注射0.8μg免疫神經(jīng)毒mu-p75-saporin適度損傷基底前腦膽堿能神經(jīng)，20天后行闌尾切除術(shù)，術(shù)后第3天水迷宮試驗(yàn)測試其認(rèn)知功能的變化。 結(jié)果：闌尾切除術(shù)對成年小鼠的空間學(xué)習(xí)和記憶能力沒有影響，但能引起老年小鼠的空間學(xué)習(xí)和記憶力下降。相應(yīng)地，手術(shù)并不改變成年小鼠海馬膽堿能神經(jīng)主要標(biāo)志物的表達(dá)，但明顯下調(diào)了老年小鼠海馬ChAT、VAChT的水平及ACh含量。應(yīng)用多奈哌齊能預(yù)防老年小鼠術(shù)后空間學(xué)習(xí)和記憶力的下降，并上調(diào)海馬內(nèi)ACh含量。而應(yīng)用mu-p75-saporin適度地?fù)p傷成年小鼠基底前腦膽堿能神經(jīng)后再行手術(shù)則會引起其學(xué)習(xí)記憶力的下降。 2、手術(shù)造成老年小鼠中樞膽堿能神經(jīng)損傷的機(jī)制研究 方法：實(shí)驗(yàn)一：為探究手術(shù)對老年小鼠中樞NGF及調(diào)節(jié)NGF生成和降解的相關(guān)蛋白的影響，老年小鼠行闌尾切除術(shù)后采用Western Blot檢測其海馬內(nèi)NGF、NGF前體蛋白（proNGF）和受體TrkA、p75NTR蛋白量的變化，，同時(shí)檢測小鼠海馬內(nèi)纖維蛋白溶酶原、組織纖溶酶原激活物（tPA）和基質(zhì)金屬蛋白酶9（MMP9）的表達(dá)變化；實(shí)驗(yàn)二：為驗(yàn)證NGF在手術(shù)引起老年小鼠中樞膽堿能系統(tǒng)損傷中的作用，給予老年小鼠雙側(cè)海馬內(nèi)注射10μg重組小鼠β-NGF，注射后30min立即行闌尾切除術(shù)，術(shù)后第3天水迷宮試驗(yàn)測試其認(rèn)知功能的變化，水迷宮結(jié)束后采用Western Blot檢測海馬膽堿能神經(jīng)主要標(biāo)志物的表達(dá)變化，包括ChAT、AChE、VAChT和CHT。 結(jié)果：手術(shù)下調(diào)了老年小鼠海馬內(nèi)NGF及其活化受體pTrkA的表達(dá)水平，但對proNGF、TrkA和p75NTR受體的表達(dá)沒有影響。同時(shí)，手術(shù)上調(diào)了MMP9的表達(dá)水平，不影響纖維蛋白溶酶原和tPA的表達(dá)。給予外源性NGF能預(yù)防手術(shù)導(dǎo)致的老年小鼠學(xué)習(xí)和記憶能力的下降，同時(shí)逆轉(zhuǎn)手術(shù)對老年小鼠中樞膽堿能神經(jīng)的損傷。 3、快速老化小鼠SAMP-8對吸入麻醉藥敏感性的研究 方法：為觀察小鼠對揮發(fā)性吸入麻醉藥的敏感性變化，采用夾尾法檢測4、6、8、10月齡快速老化小鼠SAMP-8和正常老化小鼠SAMR-1異氟醚、七氟醚及地氟醚的最低肺泡有效濃度（MAC）值。 結(jié)果：統(tǒng)計(jì)學(xué)分析表明年齡和品系因素對MAC值均有影響，SAMP-8小鼠三種吸入麻醉藥的MAC明顯低于SAMR-1小鼠，并且隨著年齡增長SAMP-8小鼠的MAC明顯降低。 結(jié)論 1、中樞膽堿能系統(tǒng)退化是造成老年動物術(shù)后認(rèn)知功能損傷的重要原因。 2、手術(shù)造成老年小鼠中樞膽堿能神經(jīng)損傷的機(jī)制可能與NGF的降解增加相關(guān)。外源性NGF能預(yù)防手術(shù)造成的老年小鼠學(xué)習(xí)和記憶能力的減退。 3、與正常老化小鼠SAMR-1相比，快速老化小鼠SAMP-8對三種常用吸入麻醉藥（異氟醚、七氟醚和地氟醚）的敏感性更強(qiáng)。
[Abstract]:Background

Postoperatively , cognitive impairment ( POCD ) is the only one in the pathogenesis of POCD , but the pathogenesis of POCD is still unknown . However , the pathogenesis of POCD is still unknown . Although old age is the only definite inducing factor of POCD , it is not clear that the degeneration of central cholinergic system can lead to the injury of cognitive function in old animals . Therefore , the relationship between the specific mechanism and nerve growth factor ( NGF ) is discussed , which provides a new idea for the prevention and treatment of POCD .

Rapid aging model mouse ( SAM ) is a kind of inbred mouse with aging model , in which SAMP - 8 strain is the ideal model for studying early neurodegenerative diseases of Alzheimer ' s disease ( AD ) .

Methods and Results

1 . Role of central cholinergic nerve degeneration in POCD of senile mice caused by operation

Methods : The changes of spatial learning and memory ability of mouse hippocampus were measured by Morris water maze test on the 3rd day after the end of the water maze . Western Blot and biochemiluminescence techniques were used to detect the changes of the main markers of cholinergic nerve in the hippocampus of mice .
Experiment 2 : In order to verify the effect of central cholinergic system on learning and memory loss of senile mice , 5 mg / kg / day old mice were given orally for 4 weeks to improve the activity of central cholinergic nerves . After the end of the stomach , appendix resection was performed on the first day . After the end of the water maze test , the changes of spatial learning and memory ability were measured in mice . Western Blot and biochemiluminescence techniques were used to detect the protein expression and the changes of the protein expression of the main marker of cholinergic nerve in hippocampus after the end of the water maze .
Experiment 3 : To further prove that the degeneration of the central cholinergic system is an important cause of memory loss in mice induced by surgery , the rats were given a moderate damage to the basal anterior cerebral cholinergic nerve in the lateral ventricle of the adult mouse . After 20 days of appendix resection , the changes of cognitive function were measured in the third Tianshui maze test .

Results : The spatial learning and memory ability of adult mice were not affected by appendix resection , but the spatial learning and memory ability of aged mice were decreased . Accordingly , the levels of ChAT and VAChT in hippocampus of aged mice were not changed .

2 . Study on the mechanism of nerve injury in the central cholinergic nerve of old mice caused by surgery

Methods : The expression of NGF , proNGF and TrkA and p75NTR protein in the hippocampus of aged mice were examined by Western Blot to investigate the changes of NGF , proNGF and TrkA and p75NTR protein in aged mice .
Experiment 2 : To verify the role of NGF in the injury of old mouse central cholinergic system caused by operation , 10 渭g recombinant mouse 尾 - NGF was injected into bilateral hippocampus of old mice . After injection , appendix resection was performed 30 min after injection . The changes of cognitive function were measured in the third day after injection . Western Blot was used to detect the changes of the main markers of cholinergic nerve in hippocampus .

Results : The expression level of NGF and its activated receptor pTrkA in the hippocampus of aged mice was regulated by surgery , but the expression of proNGF , TrkA and p75NTR receptors was not affected . At the same time , the expression level of MMP - 9 was raised , and the expression of plasminogen activator was not affected .

3 . Study on the sensitivity of SAMP - 8 to inhalation anesthetics in mice with rapid aging

Methods : To observe the sensitivity of mice to volatile inhalation anesthetics , the minimum alveolar effective concentration ( MAC ) values of SAMP - 8 and normal aging mice ( SAMP - 8 ) and normal aging mice ( SAMP - 1 isoflurane , heptafluoroether and desmethyl ether ) were determined by means of clip - tail method .

Results : The statistical analysis showed that age and strain factors had a significant influence on MAC values . The MAC of three inhaled anesthetics in SAMP - 8 mice was significantly lower than that of SAMR - 1 mice , and the MAC of SAMP - 8 mice decreased with age .

Conclusion

1 . The degeneration of central cholinergic system is an important cause of impairment of cognitive function in old animals .

2 . The mechanism of nerve injury in the central cholinergic nerve of old mice caused by the operation may be related to the increase of NGF . Exogenous NGF can prevent the aging mice from learning and memory loss caused by operation .

3 . Compared with normal aged mouse SAMR - 1 , the sensitivity of SAMP - 8 to three commonly used inhalational anesthetics ( isoflurane , heptafluoroether and desmethyl ether ) was stronger than that of normal aging mice .

【學(xué)位授予單位】：上海交通大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2014
【分類號】：R614

【參考文獻(xiàn)】

相關(guān)期刊論文 前2條

1 皋源,張挺杰,王祥瑞,杭燕南;體外循環(huán)心臟手術(shù)后精神障礙發(fā)生率及相關(guān)因素[J];上海第二醫(yī)科大學(xué)學(xué)報(bào);2004年11期

2 曹建國;洪濤;聞大翔;皋源;萬燕杰;刁樞;李立志;杭燕南;孫大金;;老年患者術(shù)后精神和認(rèn)知障礙的發(fā)病率及相關(guān)因素分析[J];上海醫(yī)學(xué);2005年11期

本文編號：1759637