【作者】 王晓君；

【导师】 魏登邦；

【作者基本信息】 青海大学 ， 动物营养， 2008， 硕士

【摘要】 高原鼢鼠和高原鼠兔是青藏高原土著动物,对低氧具有很好的适应性。为了探讨在低氧环境中两者肺细叶结构的适应特征,应用体视学方法测量了肺细叶相关指标。结果发现,高原鼢鼠和高原鼠兔肺单位面积肺泡数显著高于SD大鼠(P<0.05),单个肺泡面积和弹性纤维/肺实质比显著低于SD大鼠(P<0.05);高原鼢鼠肺泡隔厚度最厚,高原鼠兔最薄,且三种动物具显著差异(P<0.05);高原鼢鼠和高原鼠兔气–血屏障的算术平均厚度(Ta)和调和平均厚度(Th)均显著低于SD大鼠(P<0.05);在三个级别的微血管中,高原鼠兔中膜肌层厚度显著低于高原鼢鼠(P<0.05),但两种高原动物均显著低于SD大鼠(P<0.05);高原鼢鼠和高原鼠兔的微血管密度(MVD)显著高于SD大鼠(P<0.05)。为了研究两者的血液学特征,用Premier GEM-3 000自动血气分析仪、Sysmex SF-3 000血细胞分析仪及聚丙烯酰胺凝胶电泳对两种高原动物的血气、血常规、血红蛋白类型及血清乳酸脱氢酶进行分析。结果发现,高原鼠兔和SD大鼠的动脉血pH明显低于高原鼢鼠(P<0.05),但三者静脉血无显著差异;高原鼠兔和SD大鼠的动、静脉血二氧化碳分压(PCO2)均低于高原鼢鼠(P<0.05),且高原鼢鼠的动、静脉血PCO2差高于另两者;高原鼢鼠动脉血氧分压PO2最高,而静脉血PO2最低,高原鼠兔的动、静脉血PO2差也高于SD大鼠;两种高原动物的动、静脉血氧饱和度差(SO2(a-v))均显著高于SD大鼠(P<0.05),但高原鼢鼠最高。高原鼢鼠和高原鼠兔的红细胞数(RBC)、红细胞压积(HCT)及平均红细胞容积(MCV)组间无显著差异(P>0.05),但高原鼢鼠和高原鼠兔的红细胞数显著高于SD大鼠,红细胞压积及平均红细胞容积均显著低于SD大鼠(P<0.05)。高原鼢鼠的血红蛋白浓度(HBC)与SD大鼠无显著差异(P>0.05),但显著高于高原鼠兔的HBC(P<0.05)。高原鼢鼠血红蛋白主要有两种类型,高原鼠兔血红蛋白主要有三种类型,而SD大鼠血红蛋白主要有五种类型。从血红蛋白电泳迁移来看,两种高原动物血红蛋白类型有明显的趋同特征并与SD大鼠具有明显的差异。高原鼠兔血清乳酸脱氢酶活力及乳酸含量均表现最高(P<0.05),而高原鼢鼠均表现最低(P<0.05)。高原鼢鼠血清乳酸脱氢酶表现五种类型,以M型为主;高原鼠兔这表现六种类型,以H型为主。以上结果表明,高原鼢鼠和高原鼠兔肺细叶结构及血液学特征表现出一定趋同,这些特征有利于在低氧条件下提高肺气体扩散容量、增加血液携氧和组织释氧能力。但是,部分指标又表现出明显的差异,可能是由不同生境和习性造成的。更多还原

【Abstract】 The Plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzniae) are species endemic to the Qinghai-Tibet Plateau.To study the adaptive characteristics of pulmonary acinus structure in the two species, we measured relative indices by using stereological methods, using the SD rats as control model. The results revealed evident difference in lung weight vs. body weight (LVB) between the three species. The LVB value was the highest in plateau zokors, and lowest in SD rats. There was no significant difference in density of pulmonary alveoli (DPA) between plateau zokors and plateau pikas, but the DPAs in the two species were higher than that in SD rats. The aera of pulmonary alveolous (APA) and elastic fiber vs. lung parenchyma (EVP) of plateau zokors and plateau pikas were significantly lower than that of SD rats. It was obviously different among thickness of interalveolar septum (TIS) of the three animals. Air-blood barrier arithmetic mean thickness (Ta) and harmonic mean thickness (Th) were both less than those in SD rats. The muscle thickness vs. the outer diameter of microvessel (MVM) and microvessel density (MVD) of plateau zokors and plateau pikas were significantly higher than those in SD rats, and there was obviously different in MVM between the two high altitude animals.To explore the adaptive mechanisms of blood in plateau zokor and plateau pika to the hypoxic environment, the blood-gas propoties, blood indices, content of lactic acid and activity of latate dehydrogenase were analyzed, meanwhile, the types of hemoglobin and lactate dehydrogenase (LDH) were analyzed by polyacrylamide gel electrophoresis. The results indicated that it was significantly different in arterial blood pH of plateau zokor with plateau pika and SD rat, but no different in venous blood pH. The partial pressure for carbon dioxide (PCO2) in arterial and venous blood of plateau zokor was the highest, and the difference of PCO2 was also higher. The partial pressure for oxygen (PO2) in arterial blood of plateau zokor was the highest, and lowest in venous blood. The difference of PO2 in arterial blood to venous blood of plateau pika was higher than that of SD rat, too. The difference of oxygen saturation in arterial blood to venous blood of the two high-altitude animals were obviously higer than that of SD rat, but that of plateau zokor was the highest. It was not significantly different in red blood corpuscle count (RBC), hematocrit (HCT), and mean corpuscular volume (MCV) between plateau zokors and plateau pikas, but the RBC of the zokors and the pikas were significantly higher, and the HCT and MCV were significantly lower than those in SD rats. The hemoglobin concentration (HBC) in plateau pikas was significantly lower than that in plateau zokors and SD rats. Two types of hemoglobin were discovered in plateau zokors, three types of hemoglobin in plateau pikas, five types of hemoglobin in SD rats. The hemoglobin types of the two high altitude animals demonstrated convergent evolution characteristics according to the electrophoresis migration, and it showed significant difference with SD rats. The activity of LDH and content of lactic acid (LD) in plateau pika were the highest, and that in plateau zokor were the lowest. Five types of LDH isozymogram in plateau zokor were discovered, LDH-M was in major, and six types in plateau pika, LDH-H was in major.In conclusion, the structures of pulmonary acinus and blood characteristics in two high altitude animals show obvious convergent evolution in long time of adapting the hypoxic environment, that make lung have strong capacity of oxygen uptake, and permit blood to have strong capacity to carry oxygen and release more in tissues. However, they have significant difference in some indices, maybe they due to the different habitats and habits.更多还原