【摘要】：雌激素是人體內主要的女性激素之一，，已有大量研究表明雌激素替代治療對中樞神經系統(tǒng)認知功能具有保護作用。而雌激素替代治療改善認知的同時對海馬及其分區(qū)體積的影響目前多為影像學研究而尚未見組織學定量數(shù)據(jù)報告，且現(xiàn)有研究結果仍存在爭議；此外現(xiàn)已知的雌激素替代治療對認知功能的改善可以通過保護海馬齒狀回神經元存活和增殖，改善神經元興奮性，增加海馬CA1區(qū)樹突棘和突觸數(shù)量等方式來實現(xiàn)，而雌激素對中老年大鼠海馬內傳導神經沖動的有髓神經纖維的作用的精確定量研究目前尚未見相關報道。因此，本實驗利用Morris水迷宮，冰凍切片技術，電鏡技術及體視學方法研究雌激素替代治療對中老年卵巢切除大鼠空間記憶能力，海馬及其CA1體積，以及CA1區(qū)內有髓神經纖維的影響，并為雌激素替代治療作用中老年卵巢切除大鼠行為學和海馬形態(tài)學提供有力的數(shù)據(jù)基礎和理論依據(jù)。 1.材料與方法 1.110月齡SD雌性大鼠切除雙側卵巢，術后一個月將大鼠隨機分為雌激素替代治療組（OVX＋E2組）（10只）和安慰劑組（OVX＋Veh組）（9只）。其中OVX＋E2組給予連續(xù)四周的17β-雌二醇皮下注射，OVX＋Veh組給予連續(xù)四周的安慰劑（芝麻油）皮下注射。雌激素替代治療后，應用Morris水迷宮對其空間參考記憶能力進行測試。 1.2Morris水迷宮測試后，分別從OVX+Veh組和OVX+E2組中隨機選取5只大鼠，灌注固定后隨機選取一側大腦半球作1mm連續(xù)切片，在解剖顯微鏡下放大10倍拍照；將切得的1mm腦片在冰凍切片機中速凍并切取一張10μm腦片做蘇木素染色顯示神經元，用以區(qū)分CA1區(qū)范圍。然后利用體視學方法對海馬及其CA1區(qū)體積進行測定。 1.3將已灌注固定的另一側大腦半球作1mm連續(xù)切片，取出包含海馬結構的腦組織切片，隨機切取1mm3海馬CA1區(qū)組織塊，每只動物取5個標本塊做成60nm的超薄切片，從每張切片上隨機取15個視野在透射電鏡下放大8000倍拍照。 1.4利用體視學方法分別對OVX+Veh組和OVX+E2組大鼠海馬CA1區(qū)有髓神經纖維長度密度及總長度、有髓神經纖維體積密度及總體積、髓鞘體積密度及總體積、軸突體積密度及總體積以及平均直徑進行定量研究。 2.結果 2.1OVX＋E2組大鼠Morris水迷宮的尋臺潛伏期明顯較OVX＋Veh組短（P＜0.05）。 2.2兩組大鼠的海馬總體積沒有顯著性改變（P=0.100）。 2.3兩組大鼠的CA1區(qū)總體積沒有顯著性改變（P=0.366）。 2.4OVX＋E2組有髓神經纖維總體積較OVX＋Veh組顯著增加了31.4%（P=0.016）。 2.5OVX＋E2組有髓神經纖維髓鞘總體積較OVX＋Veh組顯著增加了37.8%（P=0.009）。 2.6OVX＋E2組有髓神經纖維軸突總體積較OVX＋Veh組增加了35.0%，兩組間不存在顯著性差異（P=0.087）。 2.7OVX＋E2組有髓神經纖維總長度較OVX＋Veh組增加了28.2%，兩組間不存在顯著性差異（P=0.105）。 2.8OVX＋E2組有髓神經纖維平均直徑較OVX＋Veh組減少了1.3%，兩組間不存在顯著性差異（P=0.828）。 全文結論 1.本研究發(fā)現(xiàn)為期四周的雌激素替代治療對中老年雌性卵巢切除SD大鼠的空間記憶能力具有顯著的保護作用。 2.本研究發(fā)現(xiàn)為期四周的雌激素替代治療能增加中老年雌性卵巢切除SD大鼠海馬CA1區(qū)有髓神經纖維總體積及有髓神經纖維髓鞘總體積。
[Abstract]:Estrogen is one of the main female hormones in human body , and there is a great deal of research that estrogen replacement therapy has protective effect on the cognitive function of the central nervous system .
The effect of estrogen replacement therapy on the spatial memory capacity , hippocampus and CA1 volume of hippocampal CA1 region and myelinated nerve fibers in CA1 region were studied by Morris water maze , frozen section technique , electron microscope technique and stereology method .

1 . Materials and Methods

1.110 month - old SD female rats were randomly divided into estrogen replacement therapy group ( 10 rats ) and placebo group ( 9 rats ) .

After 1 . 2Morris water maze test , 5 rats were randomly selected from the group of the ovariectomized + Veh group and the ovariectomized + E2 group , and 1 mm continuous slices were randomly selected on one side of the cerebral hemisphere after the perfusion fixation , and the images were magnified 10 times under an anatomical microscope ;
A slice of 1 mm slices were quickly frozen in a frozen slicer and a 10.mu . m slices of brain slices were cut to show neurons to distinguish the CA1 region . Then , the volumes of the hippocampus and CA1 region were measured by stereology .

1.3 slices of the brain tissue containing the sea horse structure are taken out and the tissue blocks of the CA1 region of the hippocampus CA1 region of the hippocampus are taken out by taking out the slices of the brain tissue containing the sea horse structure , and each animal takes 5 specimen blocks to be made into ultrathin sections of 60nm , and 15 fields of view are randomly taken from each slice to be enlarged by 8000 times to take pictures under transmission electron microscope .

1.4 The density and total length of myelinated nerve fibers , the volume density and total volume of myelinated nerve fibers , the volume density and total volume of myelin sheath , the volume density and the total volume of myelinated nerve fibers and the mean diameter were studied by stereology .

2 . Results

2 . The latency period of the Morris water maze was shorter than that in the ovariectomized rats ( P < 0.05 ) .

2 . There was no significant change in the total volume of hippocampus in the two groups ( P = 0 . 100 ) .

2 . There was no significant change in the total volume of CA1 region in both groups ( P = 0.366 ) .

2 . The total volume of myelinated nerve fibers increased significantly ( P = 0 . 016 ) .

The total volume of myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated myelinated nerve fibers increased by 38.8 % ( P = 0 . 009 ) .

There was no significant difference between the two groups ( P = 0.087 ) .

There was no significant difference between the two groups ( P = 0.105 ) .

There was no significant difference between the two groups ( P = 0.828 ) .

full - text conclusion

1 . The study found that the four - week estrogen replacement therapy had a significant protective effect on the spatial memory ability of female ovariectomized female SD rats .

2 . The study found that the four - week estrogen replacement therapy could increase the total volume of myelinated nerve fibers and the total volume of myelinated nerve fibers in CA1 region of SD rats .
【學位授予單位】：重慶醫(yī)科大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：R749.16

【相似文獻】

相關期刊論文 前10條

1 劉同慎;有髓神經纖維縱切片的制作方法[J];解剖學雜志;2000年01期

2 楊姝;李琛;張偉;汪維偉;唐勇;;大鼠大腦白質及白質內有髓神經纖維老年性改變的體視學研究[J];解剖學報;2007年06期

3 徐tr;李琛;楊姝;張偉;盧偉;唐勇;;運用新的體視學方法研究大鼠胼胝體及胼胝體額區(qū)有髓神經纖維[J];第三軍醫(yī)大學學報;2009年01期

4 徐tr;楊姝;李琛;張偉;盧偉;唐勇;;大鼠胼胝體體積和胼胝體額區(qū)有髓神經纖維老年改變[J];解剖學雜志;2009年02期

5 閔琦s

本文編號：2130665