SPF级与普通级新西兰兔血液学参数的比较

目的对普通级新西兰兔进行剖宫产,获得SPF兔,比较SPF兔和普通级兔血液学参数。方法采取剖宫产手术培育成无菌兔,接种正常寄生菌使之SPF化。耳缘静脉采血,自动生化分析仪测定SPF兔、普通级兔血液学参数。结果经检测SPF兔符合国家SPF兔标准;SPF兔和普通级新西兰兔白细胞数、血红蛋白、红细胞容积、中性粒细胞百分比、嗜酸性粒细胞百分比、嗜碱性粒细胞百分比、中性粒细胞数、单核细胞数、嗜酸性粒细胞数、嗜碱性粒细胞数、总蛋白、球蛋白、白蛋白/球蛋白、谷酰转肽酶、葡萄糖、钙、高密度脂蛋白胆固醇等参数差异极显著（P〈0.01）;血小板数、淋巴细胞百分比、肌酐差异显著（P〈0.05）;红细胞数、平均红细胞体积、平均血红蛋白含量、平均血红蛋白浓度、红细胞体积分布宽度、平均血小板体积、单核细胞百分比、淋巴细胞数、白蛋白、丙氨酸转氨酶、天冬氨酸转氨酶、总胆红素、碱性磷酸酶、尿素氮、尿酸、磷、总胆固醇、甘油三酯、低密度脂蛋白胆固醇、磷酸肌酸激酶、乳酸脱氢酶差异不显著（P〉0.05）。结论不同等级微生物环境对新西兰兔血液学指标有显著影响。     

树鼩解剖数据的测定与分析

解剖数据是实验动物主要的生物学特性指标。该文对实验室驯养树鼩(7～9月龄)的体尺、骨骼、乳头、肠道及脏器重量与系数等解剖学数据进行了测定与分析。31项解剖数据测量结果显示雌、雄个体间体高、右耳宽、回肠及结肠差异显著(P<0.05),体斜长、胸深、躯干长、左右两前肢长、右后肢长、左右两侧耳长、左耳宽、龙骨长、左右两侧胫长、十二指肠及空肠长等差异极显著(P<0.01)。以体长为因变量,尾长、躯干长、左前肢长、右前肢长、左后肢长及右后肢长等为自变量作逐步回归分析,回归方程为:体长=13.90+尾长×0.16。37项脏器及系数测定结果:雌雄间比较,体重、心、肺、脾、左肾、右肾、膀胱、左海马、右海马、左颌下腺、左甲状腺、右甲状腺重量差异极显著(P<0.01)。小肠、右颌下腺、左肾上腺之间差异显著(P<0.05);心、肺、胃、膀胱、小肠、大肠、脑、右海马、左肾上腺系数雌雄间差异极显著(P<0.01)。右肾、左海马、左颌下腺、右肾上腺、左右两侧甲状腺系数之间达到了显著性水平(P<0.05)。以动物体重为因变量,以主要脏器指标:心脏、肺、肝、脾、左肾、右肾、脑为自变量,作逐步回归分析,回归方程为:体重=62.73+左肾×79.213+心脏×24.09。实验室驯养树鼩不同性别对体尺、脏器及系数、肠道等解剖数据有一定影响,为树鼩实验动物化及人类疾病动物模型研究提供基础数据。     

SPF级与普通级小型猪主要脏器形态与脏器系数比较

目的比较两种不同微生物学控制等级的五指山小型猪主要脏器重量和相对重量差异。方法选取4月龄近交培育的五指山猪20头,其中普通级和SPF级各10头,雌雄各半,分别测定体重和7种主要脏器重量,分析两种不同微生物控制程度的小型猪主要脏器形态及脏器相对重量。结果SPF级小型猪体重显著低于普通级对照（P〈0.01）,前者肺和脾的形态发生改变,肝、心、脑和肾上腺的相对重量显著高于普通级对照（P〈0.01）,而SPF级的脾和肺的相对重量显著低于普通级对照（P〈0.01）。结论小型猪在不同微生物控制程度下体重和脏器系数存在显著差异,主要脏器形态与脏器系数差异可作为实验动物质量鉴定的参考依据。     

GF昆明小鼠主要重量系数及血液生理指标的测定

目的测定无菌KM小鼠体重、体长、尾长、脏器系数、血常规值。方法选取8只全雄无菌KM小鼠,8只SPF级测量体重、体长、尾长;检测红细胞总数(RBC),血红蛋白(HGB),红细胞压积(HCT),平均红细胞体积(MCV),血小板总数(PLT),白细胞总数(WBC),白细胞分类(DLC),平均血红蛋白含量(MCH),平均血红蛋白浓度(MCHC)等血液生理指标;解剖采集小鼠心脏、肝脏、脾脏、肺、肾、睾丸、盲肠,称重,计算脏器系数(脏器系数=脏器湿重/体重×100)。结果体长、尾长、心脏、脾脏、肺、肾脏、脑、睾丸、及血液生理指标等项目差异无统计学意义(P>0.05),体重、肝脏、盲肠项目差异有统计学意义(P<0.05)。结论所测数值为研究者提供基础数据,建立国内无菌KM小鼠背景资料。     

野生成年树鼩主要脏器重量及脏器系数的测定分析

目的对野生成年树鼩的体重和主要脏器重量进行测定,计算其脏器系数。方法测定60只野生成年树鼩体重及11个主要脏器重量,并计算其脏器系数。进行脏器重量、脏器系数的性别间比较分析及Kendall和谐系数分析。结果性别间比较心、肺重量差异极显著（P〈0.01）,脑、肾上腺、胰腺重量之间差异显著（P〈0.05）;肾上腺、胰腺系数差异有极显著性（P〈0.01）,心、肺、肾系数之间差异均达到了显著水平（P〈0.05）。Kendall和谐系数（W）分析表明,动物与其个体各主要器官整体发育协调性较好。结论野生成年树鼩心重量、肺重量、脑重量、肾上腺重量、胰腺重量、肾上腺系数、胰腺系数、心系数、肺系数、肾系数性别间存在差异。     

高寒地区高原鼠兔消化道形态的季节动态

对青藏高原高寒地区的高原鼠兔在自然环境中消化道各器官的长度及重量的季节变化进行了测定。结果表明,总消化道长度和含内容物组织重保持相对的稳定性,而组织鲜重和干重则季节性变化明显,均于条件较恶劣的草枯黄期达最大值;除含内容物组织重于草生长盛期较高外,胃的变化相对比较稳定。小肠的变化最为剧烈,各项指标均显示明显的季节变化,表明该器官对环境因素的改变反应强烈,各指标一般于草枯黄期和草生长盛期较高;盲肠的干重于草枯草显著增加,其它指标基本维持稳定;大肠的长度于草枯黄期显著增加,草生长盛期较高;盲肠的干重于草枯黄期显著增加,其它指标基本维持稳定;大肠的长度于草枯黄期显著增加,而其它指标则并无明显的季节变化。表明在自然环境中,面对寒冷和食物质量降低等因素的胁迫,消化道各器官在不同时期产生不同的反应,且反应的程度也不同。消化道形态的调节在高原鼠兔的消化对策中占有一定的地位。     

高原鼢鼠内脏器官与海拔的相关性研究

小型哺乳动物内脏器官的质量和消化道长度具有高度可塑性,是其对环境适应的重要指标。本研究通过对高原鼢鼠内脏器官随海拔梯度变化的比较研究,旨在从形态结构方面来探讨高原鼢鼠对环境和低氧的适应机制。结果显示,雄性高原鼢鼠心脏湿重和干重、脾脏干重、肺干重、胃湿重和干重、盲肠湿重与海拔呈显著或极显著正相关,而肾湿重、大肠长度与海拔呈负相关;雌性高原鼢鼠心脏湿重和干重、肺脏湿重和干重、胃湿重、盲肠湿重、盲肠长度与海拔呈显著或极显著正相关,肝脏湿重和干重、脾脏干重、肾脏湿重和干重、大肠干重、大肠长度与海拔呈显著或极显著负相关;其他与海拔无显著相关性。研究结果表明,内脏器官与海拔的相关性体现出高原鼢鼠面对不同的生存环境、能量需求、氧气含量、外界病原体等因素做出的代偿性适应。     

无菌猪生长、血液以及脏器相关指标的测定

目的建立无菌太湖猪多项生理数据背景资料。方法对4头25 d无菌猪和4头同窝普通级群体,雌雄比3∶1,测定并比较血液常规、生化、免疫球蛋白和主要脏器发育指标。运用异速生长建模,对主要脏器重量相对体重的异速生长进行了分析。结果 (1)无菌猪与普通级猪的12项血常规和8项血生化指标差异有显著性(P0.05);(2)无菌猪与普通级猪的平均体重、血清中Ig M表达量差异达到显著性水平(P0.05),且无菌猪缺少肠系膜淋巴结;(3)无菌猪的心脏、脾和胃与体重呈负异速生长(异速生长指数b1),肠道与体重的异速生长指数为1.78,为正异速生长;而普通级猪的心脏、胃和肠道与体重呈负异速生长(b1),肾与体重的异速生长指数最大,为1.20,呈正异速生长。结论微生物学等级差异影响了猪体重、血液及脏器、免疫系统的发育。     

封闭群FMMU白化豚鼠主要脏器重量及脏器系数的测定

本文报告了２０日龄ＦＭＭＵ白化豚鼠１０个主要脏器重量和１０个脏器系数的测定结果。ＦＭＭＵ白化豚鼠按雌雄分组试验,对两组测定结果进行了对照分析,并与对照组同龄三色花豚鼠的测定结果做了比较。结果表明雄性ＦＭＭＵ白化豚鼠肾、脾、肝、心、肺的重量均明显高于雌性ＦＭＭＵ白化豚鼠,雄性白化豚鼠脑的脏器则低于雌性白化豚鼠,其它项目两者差异不显著;ＦＭＭＵ白化豚鼠与三色豚鼠比较结果表明,白化豚鼠除肾上腺、睾丸重量明显高于三色豚鼠外,其余脏器重量及全部脏器系数,相差不显著。     

牛泡沫病毒中国株感染兔的研究

将牛泡沫病毒(BFV3026)感染的细胞经耳缘静脉注射兔子,并以正常细胞注射的兔为对照。1年后处死,病毒挽救实验及PCR检测显示：兔经一次注射即可被BFV3026感染,病毒广泛分布于感染兔的多种脏器中,通过共培养可从感染兔血、肝、脾、肺、肾中拯救出相应感染性病毒颗粒,并在脑、骨髓、心、胰、肠系膜中检到高拷贝BFV原病毒DNA存在。同时,血清学检测表明：感染兔在接受注射一个月后即产生高滴度抗病毒蛋白抗体,并维持该滴度水平直至实验终止,兔未表现任何可观病变。     

Extraglandular hormonal steroidogenesis in aged rats

We have examined the metabolism in vitro of [4-¹⁴C]pregnenolone by the following organs of 2.4-year-old rats: submandibular gland, stomach, duodenum, liver, lung, heart, spleen, kidney, skin, prostate, testis and adrenal. All tissues converted pregnenolone to progesterone, the highest yields being observed with adrenal, testis and skin. Androgen formation was intense in the testis and absent in the adrenal. Moreover, 17-hydroxylation of pregnenolone occurred moderately in kidney, skin and submandibular gland and markedly in duodenum and stomach, which also produced high amounts of dehydroepiandrosterone and/or 5-androstene-3β,17β-diol. Extratesticular synthesis of androstenedione and testosterone was very low. A significant formation of 20-dihydropregnenolone was observed in all tissues but stomach, duodenum and steroidogenic endocrines. Corticosteroids were not synthesized extraadrenally, except a small amount of 11-deoxycorticosterone in the testis. These results indicate that key steroid-biosynthetic enzymes, such as 3β-hydroxysteroid dehydrogenase/Δ⁵′Δ⁴ isomerase, 17β- and 20-hydroxysteroid dehydrogenases and steroid 17-monooxygenase/17,20-lyase are also expressed extraglandularly in the rat.     

Nutritional and sanitary statuses alter postweaning development of caecal microbial activity in the rabbit

The postweaning development of caecal microbial activity was studied in the rabbit according to the sanitary status (conventional "C" vs. specified pathogen-free "SPF") and the nutritional status (standard-fibre "SF" vs. deficient-fibre "DF" diet). The two diets were distributed ad libitum from weaning (28 days) to 70 days of age, respectively, to 80 C and 72 SPF rabbits. From 28 to 42 days, the volatile fatty acids concentration in the caecum (tVFA) of C rabbits was 50 mM/L and increased by 46% between 42 and 56 days, without interactions with the diet effect. In parallel, the bacterial fibrolytic activity decreased for xylanase and CMCase (-32% and -60%, respectively, P<0.05), while pectinase activity decreased more regularly from 28 to 70 days (-28%, P<0.05). At weaning, tVFA was similar among C or SPF rabbits, while at 70 days, it decreased by 23% for SPF and increased in C group (+31%). Cellulasic and hemicellulasic activity of bacteria were two to three times lower, respectively, in SPF rabbits compared to conventional ones. No interaction was detected between sanitary and nutritional status at 70 days of age for the caecal fermentative activity. With the FD diet, tVFA decreased by 10%, while butyrate proportion increased by 37% (at 70 days), whatever the sanitary status. In 70-day-old rabbits (C or SPF group), pectinasic activity was reduced by 30% when rabbits were fed the FD compared to the SF one.     

Establishment of specific pathogen-free rabbit colonies with limited-flora rabbits associated with conventional rabbit flora, and monitoring of their cecal flora.

In the present study we attempted to establish specific-pathogen-free (SPF) rabbit breeding colonies with two groups of limited-flora (LF) rabbits, both ex-germfree rabbits, and their offspring. Two groups of LF rabbits associated with cecal flora of conventional (CV) rabbits produced in a previous study [Exp. Animals, submitted], were transferred to individual barrier rooms and some of the LF rabbits were accommodated in isolators to maintain the basic flora for SPF rabbits. The composition of the cecal flora of LF rabbits was stable for a long period; bacteroides remained predominant and clostridia dominant. From the SPF rabbits, different types of bacteria, e.g., enterobacteriaceae and streptococci, which could not be isolated in the isolator were detected at a low population level at an early stage in the establishment of the SPF colonies, but the basic composition of the cecal flora was mainly bacteroidaceae and clostridia and did not change over a long period, and the floral composition became similar to that of CV rabbits. The fertility and weaning rates of the SPF rabbits were satisfactory for a SPF rabbit colony. In addition, these SPF colonies were free of more than one year rabbit-specific pathogens.     

Rearing of germfree rabbits and establishment of an SPF rabbit colony]

Baby rabbits hysterectomy-derived from conventional Japanese white rabbits were reared under aseptic condition by feeding with 4 types of artificial diets. Rabbit milk for the artificial diet was obtained from conventional dams at 7--25 days after delivery. The artificial diets was given by stomach tube twice a day. The total volumes of diet given (ml per day) were Y = 2.3X + a (1 to approximately 14 days of age), Y = 32.2 + a (l5 to approximately 25 days of age), or Y = (32.2 + a) - 37.5 (X - 25) (26 to approximately 34 days of age), (X = age in days, a = volumes fed at 0 day of age). After 14 days of age young animals were also fed freely sterilized commercial pellets and weaned at 35 days of age. Out of 155 rabbits, 130 were aseptically reared till 36 approximately 40 days of age, and no difference on weaning rate was seen between the 4 groups of rabbits. Thereafter, they were exposed to a barriered room of SPF rabbitry outside the isolators. The best growth was seen in animals given by artificial diet containing rabbit milk at 40%. The SPF breeding colony of rabbits was found to be free of Pasteurella pneumotropica, Bordetella bronchiseptica, Salmonella spp., Eimeria spp., Encephalitozoon cuniculi and Acaritic otistis.     

Broad expression of fructose-1,6-bisphosphatase and phosphoenolpyruvate carboxykinase provide evidence for gluconeogenesis in human tissues other than liver and kidney

The importance of renal and hepatic gluconeogenesis in glucose homeostasis is well established, but the cellular localization of the key gluconeogenic enzymes liver fructose-1,6-bisphosphatase (FBPase) and cytosolic phosphoenolpyruvate carboxykinase (PEPCK) in these organs and the potential contribution of other tissues in this process has not been investigated in detail. Therefore, we analyzed the human tissue localization and cellular distribution of FBPase and PEPCK immunohistochemically. The localization analysis demonstrated that FBPase was expressed in many tissues that had not been previously reported to contain FBPase activity (e.g., prostate, ovary, suprarenal cortex, stomach, and heart). In some multicellular tissues, this enzyme was detected in specialized areas such as epithelial cells of the small intestine and prostate or lung pneumocytes II. Interestingly, FBPase was also present in pancreas and cortex cells of the adrenal gland, organs that are involved in the control of carbohydrate and lipid metabolism. Although similar results were obtained for PEPCK localization, different expression of this enzyme was observed in pancreas, adrenal gland, and pneumocytes type I. These results show that co-expression of FBPase and PEPCK occurs not only in kidney and liver, but also in a variety of organs such as the small intestine, stomach, adrenal gland, testis, and prostate which might also contribute to gluconeogenesis. Our results are consistent with published data on the expression of glucose-6-phosphatase in the human small intestine, providing evidence that this organ may play an important role in the human glucose homeostasis.     

Differential expression of phospholipases D1 and D2 in mouse tissues

The differential expression of phospholipase D (PLD) isozymes, which include PLD1 and PLD2, was examined in various murine tissues, including the cerebrum, cerebellum, heart, lung, liver, spleen, stomach, pancreas, ileum, colon, adrenal gland, kidneys, testes, ovaries, and uterus. In Western blot analysis, only PLD1 was detected in the heart and ovary, while only PLD2 was detected in the pancreas and ileum. Both PLD1 and PLD2 were strongly expressed in the cerebrum, cerebellum, and lung, and both were also expressed in the liver, spleen, stomach, colon, kidney, testes, and uterus. Immunohistochemistry showed intense PLD immunostaining in the cerebrum, cerebellum, lungs, intestines, and testis, and weak PLD immunostaining in the liver, kidneys, spleen, and heart. These findings suggest that PLD1 and PLD2 are differentially expressed in the various organs of mice, and that each PLD isozyme plays a distinct role in each organ.     

Cholesterol synthesis in vivo and in vitro in the WHHL rabbit, an animal with defective low density lipoprotein receptors

These studies were undertaken to measure rates of synthesis of digitonin-precipitable sterols in vivo and in vitro in control rabbits (New Zealand (NZ) control) and in homozygous Watanabe heritable hyperlipidemic rabbits (WHHL) that lack receptors for low density lipoproteins (LDL). The plasma cholesterol concentration in NZ control fetuses equaled 79 mg/dl, rose to 315 mg/dl 12 days after birth, and fell to 80 mg/dl in young adult animals. At these same ages, cholesterol concentrations in the WHHL animals equal 315, 625, and 715 mg/dl, respectively. The rate of whole animal sterol synthesis in vivo, expressed as the mumol of [3H]water incorporated into sterols per hr per kg of body weight, was lower in the WHHL animals than in the NZ controls both in the fetuses (108 vs 176) and in the adult animals (48 vs 66). In adult NZ controls the content of newly synthesized sterols (rate of sterol synthesis) per g of tissue was highest in the liver (538 nmol/g per hr), adrenal gland (438), small bowel (371), and ovary (225) while lower rates of synthesis were found in 15 other tissues. In the WHHL rabbits a higher content of [3H]sterols was found only in the adrenal gland (2,215) while synthesis was suppressed in the liver (310), colon, lung, and kidney, and was unchanged in the remaining organs. These findings were confirmed by measurements of rates of sterol synthesis in the same tissues in vitro. When whole organ weight was taken into consideration, the tissues that were the major contributors to whole body sterol synthesis in both types of rabbits were liver, small bowel, skin, and carcass. However, it was the lower rate of synthesis in the liver of the WHHL animals that alone accounted for the lower rate of whole animal sterol synthesis seen in these rabbits. These studies demonstrate that in WHHL animals that lack LDL receptors and that have very high levels of circulating LDL cholesterol, the rate of cholesterol synthesis in nearly all tissues is normal but in the liver is significantly suppressed. Only the adrenal gland manifested enhanced synthesis. Such findings suggest that in the WHHL rabbit where LDL receptor activity is reduced and plasma LDL levels rise, mechanisms other than receptor-mediated LDL uptake may act to deliver cholesterol to the cells of the various organs and to the liver.