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1.
吗啡对福尔马林引起大鼠海马内IL-2RβmRNA表达的影响   总被引:1,自引:0,他引:1  
Wu X  Li HD  Li XC  Ruan HZ  Wang J 《生理学报》1998,50(5):591-594
本实验采用原位杂交法观察足底注射福尔马林(For)痛敏对海马内白细胞介素2受体βmRNA(IL-2RβmRNA)生成的影响及其与吗啡、促肾上腺皮质激素(ACTH)的关系。结果表明:正常大鼠海马有IL-2RβmRNA表达,集中分布于CA1-CA4区神经元、齿状回颗粒细胞。足底注射For后6h双侧海马IL-2RβmRNA表达均增加(P〈0.05),12h达高峰,24h仍高于正常。在6h时,腹腔注射吗啡  相似文献   

2.
杨晓明  谢玲 《生理学报》1997,49(5):599-601
肝再生增强因子(ALR)是一种新的肝增殖刺激因子。本研究选择70%肝部分切除(PH)大鼠为模型,观察了PH后残存肝组织胞浆液促肝细胞增殖活性与ALR特异mRNA表达动态变化的关系。发现正常肝组织几无ALR mRNA表达,其肝胞质液也无促肝细胞增殖活性;70%PH后12h肝组织ALR mRNA表达明显增加,并于术后24h达高峰,肝胞质液活性也于术后24h内达高峰,这种mRNA表达-效应的时间关系提示  相似文献   

3.
为了揭示顺义农田黑线姬鼠和大仓鼠两大害鼠种群繁殖力存在的差异及其对种群数量变化的影响,从而为制定科学灭鼠策略提供依据,1994-2014年,采用夹线法于每年3~11月(或1~12月)进行调查,每月上旬在5个监测点农田布放鼠夹500夹夜。捕获的样本测量体重、体长、尾长、耳高、后足长,解剖观察繁殖情况。以种群繁殖力为指标,分析黑线姬鼠与大仓鼠在繁殖力方面的差异,由此揭示出黑线姬鼠具有更强的竞争优势。黑线姬鼠和大仓鼠每年都有2个繁殖高峰期,并以成年以上个体为繁殖主体,分别占总胎仔数的94.5%和95.6%。黑线姬鼠的繁殖期和主要繁殖期均比大仓鼠延长1个月,且主要繁殖期的雌、雄繁殖鼠占比均高于大仓鼠,胎次数是大仓鼠的1.7倍,仅平均胎仔数低于大仓鼠,由此说明黑线姬鼠种群的繁殖力比大仓鼠更强,具有更大的竞争优势。  相似文献   

4.
根据生活史理论,免疫功能与产热和繁殖等其他生理学功能类似,具有能量代价。然而,关于提高免疫能力的能量学代价的实验例证很少,且此类代价可能受所选择的免疫学参数和实验测定的影响。为探究提高小型哺乳动物免疫能力的能量学代价,以匙孔血蓝蛋白(Keyhole limpet haemocyanin,KLH)作为外源抗原刺激,在注射前(第0天)、注射后第5天和第10天,分别测定非繁殖期雌、雄性黑线仓鼠(Cricetulus barabensis)体重和静止代谢率(Resting metabolic rate, RMR)的变化,通过眼眶静脉丛采血技术和ELISA分析,分别测定第5天(抗IgM抗体)和第10天(抗IgG抗体)动物血清抗体含量的变化。结果显示:(1)雄鼠的体重高于雌鼠,雌、雄鼠实验组和对照组之间的体重均无差异且不随时间而增加;(2)无论雌鼠还是雄鼠,注射KLH组血清中抗IgM和抗IgG抗体的含量均高于注射生理盐水的对照组动物;(3)注射KLH前后,RMR既无性别差异,也无组间差异,同一组动物的RMR均不随取样时间点而变化(KLH注射后第5天和第10天)。结果表明,单一的KLH刺激激活了黑线仓鼠的体液免疫,但在能量不受限的情况下不影响体重和能量收支的变化。有两种可能的解释:黑线仓鼠增强的体液免疫可能以免疫系统内另一免疫组分活动的降低作为代价,或它对体液免疫应答具有构建能力,温和的免疫刺激不伴随额外的能量学代价。  相似文献   

5.
本文就植物血细胞凝集素(PHA)作用的不同时间对小鼠脾脏淋巴细胞γ-谷氨酰基转肽酶(γ-GT)活性的影响进行了观察。结果表明,脾脏淋巴细胞转化率随给予PHA时间的延长而上升,对照组<24h组<48h组<72h组;淋巴细胞γ-GT活性于24h明显强于对照组(P<0.001),随着PHA作用时间的延长其γ-GT活性逐渐下降,即48h组与对照组已无显著差异,而72h组却低于对照组(P<0.001)。可见PHA在小鼠体内对γ-GT活性有很大影响。  相似文献   

6.
本实验观察了80只家兔在急性缺氧6、12、24、48;60、71h后肺指数、血浆心钠素(ANP)、抗利尿激素(AVP)、醛固酮(ALD)及尿量的变化。结果表明:在缺氧24-72h,肺指数明显升高,尿量减少、缺氧16h,血浆ANP明显升高;而缺氧48和60h无ANP升高现象。缺氧72h,血浆ANF又明显高于缺氧前水平;血浆ACP只在缺氧24h明显升高;血浆ALD未见显著性变化。这些结果提示:在缺氧状  相似文献   

7.
曹静  王桂英  赵志军 《生态学报》2016,36(15):4824-4831
为探讨环境温度和繁殖经历对黑线仓鼠哺乳期能量收支的影响,将连续3次繁殖的黑线仓鼠暴露于温度梯度降低的条件下(30—0℃,1℃/4d),使初次、第2和3次繁殖的动物分别暴露于30—20℃、20—10℃、10—0C℃,测定了哺乳期能量收支。与初次繁殖的动物相比,第3次繁殖组动物的摄食量显著增加,静止代谢率、非颤抖性产热、褐色脂肪组织细胞色素c氧化酶(COX)活性和血清T3水平显著增加,而断乳时胎仔重显著降低。结果表明:(1)低温下繁殖的黑线仓鼠处于负能量平衡,在自身维持和哺育后代的能量分配之间存在权衡,低温下产热增加,繁殖输出减少;(2)黑线仓鼠可能感知环境温度的变化,在连续降低温度的条件下降低繁殖投资,符合"季节性投资假说"的预测。  相似文献   

8.
本实验观察了80只家兔在急性缺氧6、12、24、36、48、60、71h后肺指数、血浆心钠素(ANP)、抗利尿激素(AVP)、醛固酮(ALD)及尿量的变化。结果表明:在缺氧24-72h,肺指数明显升高,尿量减少;缺氧16h,血浆ANP明显升高;而缺氧48和60h无ANP升高现象。缺氧72h,血浆ANF又明显高于缺氧前水平;血浆AVP只在缺氧24h明显升高;血浆ALD未见显著性变化。这些结果提示:在缺氧状态下,ANP、AVP的释放均与缺氧暴露的时间有关。这些激素的平衡失调可能与急性缺氧性肺水肿的发生有关。  相似文献   

9.
人类疱疹病毒6型感染细胞免疫学特性研究   总被引:2,自引:0,他引:2  
赵蓓  姚坤 《Virologica Sinica》1998,13(3):232-236
采用间接免疫荧光法、APAAP法及MTT法,研究了人类疱疹病毒6型(HHV6)中国南京地方株CN5感染细胞病毒抗原表达的形态学和动力学特征、CD抗原表达阳性细胞百分率的变化及PHA诱导的细胞增殖反应的改变。结果显示,CN5感染脐血单个核细胞(CBMCs)后8~12h即可在细胞内检出病毒抗原,至接种后48h,病毒抗原阳性细胞可达36%;CN5感染CBMCs和成人外周血单个核细胞(PBMCs)后可引起两者CD3阳性细胞减少、CD4阳性细胞增多,而对CD2、CD8、CD45RA阳性细胞百分率未见明显影响;CN5感染细胞裂解液对PHA诱导的PBMCs增殖反应具有抑制作用,这种抑制作用与该裂解液的蛋白浓度之间呈一剂量依赖关系,且可被HHV6抗血清所逆转。  相似文献   

10.
林麝妊娠期和哺乳期的能量代谢特征   总被引:17,自引:5,他引:12  
林忠  徐宏发 《兽类学报》1995,15(2):98-105,112
本文对饲养条件下林麝妊娠期和哺乳期的能量需要和行为特征进行了研究。结果表明,妊娠初期和妊娠后期能量摄取量分别比孕前增加了48.9%和95.6%。哺乳期总摄入能比妊娠期分别高2.27倍(双胎)和1.89倍(单胎)。根据在繁殖期对麝的行为观察,我们推断:麝是通过增加采食时间来增加能量的摄取,并通过减少活动,增加躺卧时间来减少能量消耗,以此满足繁殖期的能量需要。这些将结果为制定麝繁殖期的饲养标准和管理措施提供了依据。  相似文献   

11.
The skin‐swelling test is a simple and widespread method used in field ecological research to estimate cellular immune responsiveness in animals. This immunoecological test is based on measuring the magnitude of tissue swelling response at specific times following subcutaneous application of an experimental pro‐inflammatory stimulant. In the vast majority of studies across vertebrate taxa, phytohemagglutinin (PHA) is used as a universal stimulant. Given the complexity of immune response activation pathways of PHA, however, interpretation of test results can be ambiguous. Goal of this study was to improve methodology of the skin‐swelling test to decrease this ambiguity. Here, we present an alternative protocol aimed at facilitating interpretation of skin‐swelling data for mammals. Based on previous evidence suggesting that mammalian T cells are readily activated by Concanavalin A (ConA) in vitro, we compared cellular immune responses in vivo to PHA and ConA as an alternative pro‐inflammatory stimulant in mice. We measured magnitude of tissue swelling and compared it with intensity of blood cell infiltration into tissue over a 72‐hour interval. Our results corroborate that PHA and ConA show important differences in both dynamics and response amplitude in rodents. ConA induces stronger swelling with a distinct leukocyte activity pattern and higher pro‐inflammatory cytokine (interleukin 6 [IL‐6] and interferon gamma[IFN‐γ]) expression than PHA during peak response (24‐h post‐treatment). Furthermore, unlike PHA, magnitude of swelling was positively associated with cellular activity (number of neutrophils infiltrating tissue) following ConA injection. We conclude that ConA is the more suitable stimulant for skin‐swelling tests in mammals. This is because of the molecular binding specificity in the two lectins, that is, ConA specifically activates T cells while PHA also triggers erythroagglutination. We propose that ConA be used in all future ecological testing in mammals as it exhibits better performance and its application facilitates immunological interpretation of skin‐swelling test results.  相似文献   

12.
Differential resource allocation in deer mice exposed to sin nombre virus   总被引:1,自引:0,他引:1  
The resource allocation hypothesis predicts that reproductive activity suppresses immunocompetence; however, this has never been tested in an endemic disease system with free-ranging mammals. We tested the resource allocation hypothesis in wild deer mice (Peromyscus maniculatus) with natural exposure to Sin Nombre Virus (SNV). Immunocompetence was estimated from the extent of swelling elicited after deer mice were injected with phytohemagglutinin (PHA); swelling is positively correlated with immunocompetence. After livetrapping deer mice, we determined their reproductive state and SNV infection status. Males were more likely to be seropositive for SNV than females (37% vs. 25%) and exhibited 10% less swelling after PHA injection. The swelling response of females differed with both infection status and reproductive condition. There was also a significant infection status by reproductive condition interaction: non-reproductive, seropositive females experienced the least amount of swelling, whereas females in all other categories experienced significantly greater swelling. The swelling response of males differed with both SNV infection status and reproductive condition, but there was no significant infection status by reproductive condition interaction. Seronegative males elicited greater swelling than seropositive males regardless of reproductive status. In contrast to the resource allocation hypothesis, these results do not indicate that reproductive activity suppresses immunocompetence of deer mice but rather suggest that chronic SNV infection reduces immunocompetence. Sex-based differences in swelling indicate that SNV modulates the immune system of female deer mice differently than it does that of males, particularly during reproduction. We propose that differences in resource allocation between males and females could result from inherent sex-based differences in parental investment.  相似文献   

13.
The influence of the major histocompatibility (B) complex and sex on the phytohaemagglutinin (PHA) wattle response was studied in 136 segregants (B2/B2, B2/B5 and B5/B5) of a fourth generation cross between inbred lines 6(1) and 15(1). At 6 weeks of age, chickens were injected with 100 micrograms purified PHA-P. Wattle thickness measurements were taken 4, 24, 48, 72 and 96 h after injection. Analysis of variance showed that 4 h after injection, males had a significantly higher response than females but the sex-genotype interaction was also significant. Females had higher responses than males 24 and 48 h after injection as a consequence of more rapid development and earlier resolution of the reaction in males. B2/B2 chickens had significantly lower responses than B5/B5 chickens 72 and 96 h after injection, signifying a faster late resolution phase in the B2/B2 genotype. The developmental and early resolution phases of the PHA wattle response were influenced by sex while the late resolution phase was influenced by B genotype.  相似文献   

14.
Reproductive state of animals frequently is overlooked when examining endocrine functions of the thyroid gland and adrenal cortex. This experiment was done to determine effects of reproductive state on basal and stimulated concentrations of thyroxine (total T4), 3,5,3'-triiodothyronine (total T3) and cortisol in serum of adult Beagle dogs. Five male, 5 anestrous, 5 proestrous, 5 diestrous, 5 pregnant and 5 lactating dogs were fasted for 18 h before each dog received 5 IU of thyrotropic hormone (TSH) i.v. and 2.2 IU/kg of body weight of adrenocorticotropic hormone (ACTH) i.m. Blood samples were collected via jugular cannulas or by jugular venipuncture at 60, 45, 30, 15 and 1 min before and 0.5, 1, 2, 3, 4, 5, 8, 12 and 24 h after injection. Concentrations of T4 were similar in serum from diestrous and pregnant bitches but were greater (P less than 0.025) than those in dogs of other reproductive states before and after treatment with TSH. Concentrations of T3 were greater (P less than 0.005) in serum from diestrous bitches before and after TSH injection than in serum from dogs of all other reproductive states. Concentrations of T3 in males, anestrus, proestrus, pregnancy and lactation did not differ. Basal concentrations of cortisol did not differ consistently among reproductive states. However, concentrations post-ACTH were different (P less than 0.05) with anestrus = diestrus greater than lactation = pregnancy = male greater than proestrus. These results indicate that reproductive state of experimental animals must be considered when studying thyroidal and adrenal functions.  相似文献   

15.
Immunocompetence, the general capacity of an individual host to mount an immune response against pathogens, is commonly assessed by the response to a challenge of the immune system by injection of phytohaemagglutinin (PHA). The response to PHA is commonly considered a reliable estimate of the T-cell mediated immune response. We investigated the temporal pattern of the PHA response in 10 rodent species from the Negev desert, Israel. We hypothesized that the temporal dynamics of the PHA response would differ among species with different natural patterns of flea parasitism. We injected PHA subcutaneously in the footpad of each rodent and measured its PHA response 6, 24 and 48 h after injection. Rodent species showed two types of PHA response. One type was rapid and characteristic of rodents that had either species-poor flea assemblages, or that are rarely attacked by fleas. This response peaked approximately 6 h after PHA injection. The second type of response was delayed and was typical of rodents that have either species-rich flea assemblages or high abundance and prevalence of fleas or both. Their response to PHA peaked 24 h after injection. Furthermore, rodents that responded promptly had a lower maximum response than rodents with a delayed response. Our results suggest the occurrence of a trade-off between intensity and latency of the PHA response and, therefore, the necessity to account for the relationship between maximum PHA response and time after injection when making interspecific comparisons of immunocompetence.  相似文献   

16.
We examined cellular immunity of adult tree swallows feeding nestlings under variable weather conditions. Birds received an injection of phytohaemagglutinin (PHA), which causes a local swelling, reflecting the strength of T-cell-mediated immunocompetence. There was a negative relationship between the immune response and the number of nestlings in the brood (range 3-6 young) which suggests that parental effort suppresses the immune function. However, there was also a strong effect of ambient temperature and food abundance (aerial insects) on immune response. Parents that received the PHA injection during cold weather and at low food abundance showed a suppressed immune response compared to birds treated during more favourable conditions. They also lost more body mass during the 24 h inoculation period, and their offspring showed reduced growth. When controlling for ambient temperature and food abundance in a multivariate analysis, there was no longer any significant effect of brood size on the parents' immune response. Three of 39 pairs deserted their broods after PHA injection. All three desertions took place when the mean ambient temperature fell below 13°C. The PHA response is known to have both heritable and environmental components; our study emphasizes its condition-dependency. Previous studies of other passerine birds have shown that high levels of parental effort may have an immunosuppressive effect. Our study indicates that weather conditions may override the effects of natural variation in parental effort, and that the PHA response is particularly influenced by short-term fluctuations in energy balance.  相似文献   

17.
Studies on the maternal transfer of photoperiodic information in mammals indicate that the daily photoperiod perceived by the mother during the gestation-lactation period is communicated to the fetus either through the placenta or via the milk. However, the impact of photoperiodic exposures during gestation and lactation on the maternal pineal and reproductive physiology has not been reported for any tropical rodent. The exposure of pregnant female Indian palm squirrels (Funambulus pennanti) to constant light (24 h light:0 h dark), constant dark (0 h light:24 h dark), long daylength (14 h light:10 h dark) or short daylength (10 h light:14 h dark) during early gestation (< 30 days) resulted in the resorption of pregnancy, while during late gestation (> 30 days), it did not interfere with the maintenance of pregnancy. Alterations in photoperiodic condition during late gestation and lactation altered the postpartum recovery process. Pineal gland activity, as assessed by pineal mass, protein content and plasma melatonin, was lowest during the breeding phase, but increased gradually after parturition until the next breeding phase. During gestation and lactation, constant light, long daylength and short daylength conditions were less effective, while constant dark condition had a profound effect in depressing pineal gland activity, which subsequently advanced postpartum recovery. Hence, lactating females under constant darkness prepare themselves for next mating much earlier than females under natural daylength (12 h light:12 h dark) conditions. Therefore, photoperiodic information, mediated via the pineal gland, may be important for maintaining gestation physiology as well as postpartum recovery in female rodents.  相似文献   

18.
The changes in anterior pituitary (AP) of pregnant and lactating dogs as compared with pituitary of animals in metestrus-anestrus phase are described with special reference to the relative proportion, topography and morphology of prolactin cells, somatotrophs, corticotrophs, thyrotrophs and gonadotrophs. For demonstration of these cells, suitable histological, histochemical and immunoenzyme cytochemical methods are used. The prolactin cells show progressive hyperplasia during pregnancy, so that at the end of this phase and during lactation, they comprise the most predominant glandular cells in AP. At the same time, they reveal massive hypertrophy with marked morphological features of high secretory activity, After transient or continous interruption of the suckling stimulus they show signs of functional inhibition on involution. The corticotrophs appear at 20. and 30. days of pregnancy to be relatively increased in number. While in the last third of pregnancy and during lactation, they only seem to be more active than those in pituitary of metestrus-anestrus dogs. The somatotrophs appear to be progressively reduced in relative number during pregnancy and lactation. However, they show some morphological signs of active secretion. The thyrotrophs did not show any morphological alterations during the different reproductive phases. The gonadotrophs reveal during pregnancy, especially at 30. day morphological signs of stimulation. On the contrary they appear atrophied during lactation. This may be a result of suckling stimulus and morphological expression of the inverse relationship in the secretion pattern of gonadotrophins and prolactin in dogs during suckling. The estrogen and progesterone levels in plasma as well as the changes in their relative concentrations may largely account for the structural changes on AP of pregnant dogs. However, neuroendocrine reflexes (e.g. suckling stimulus) seem to be of a great importance for the maintainance of stimulation of prolactin cells during lactation.  相似文献   

19.
As a model for studying methamphetamine (MAP) abuse, which has become a social problem in Japan, we investigated the changes in serum cortisone, NK cell activity and mitogenic response of T-lymphocytes after a single injection of MAP (3.0 mg/kg) in female cynomolgus monkeys. Serum cortisol concentration was significantly elevated to 2.66 times pre-injection levels at 6 h post-injection, and the effect was still observed 24 h later. NK cell activity was significantly elevated at 6 h after MAP injection, but at 24 h after injection had dropped markedly to 49.5% of baseline. Mitogen (PHA) response of lymphocytes was elevated when MAP was injected, and this increased level continued up to 24 h. We speculate that the transient increase in NK cell activity followed by a distinct drop, as well as the changes in T-lymphocytes, may be strongly related to the cortisone concentration.  相似文献   

20.
Xu YC  Yang DB  Wang DH 《PloS one》2012,7(5):e37182
Life history theory assumes there are trade-offs between competing functions such as reproduction and immunity. Although well studied in birds, studies of the trade-offs between reproduction and immunity in small mammals are scarce. Here we examined whether reduced immunity is a consequence of reproductive effort in lactating Brandt's voles (Lasiopodomys brandtii). Specifically, we tested the effects of lactation on immune function (Experiment I). The results showed that food intake and resting metabolic rate (RMR) were higher in lactating voles (6≤ litter size ≤8) than that in non-reproductive voles. Contrary to our expectation, lactating voles also had higher levels of serum total Immunoglobulin G (IgG) and anti-keyhole limpet hemocyanin (KLH) IgG and no change in phytohemagglutinin (PHA) response and anti-KLH Immunoglobulin M (IgM) compared with non-reproductive voles, suggesting improved rather than reduced immune function. To further test the effect of differences in reproductive investment on immunity, we compared the responses between natural large (n≥8) and small litter size (n≤6) (Experiment II) and manipulated large (11-13) and small litter size (2-3) (Experiment III). During peak lactation, acquired immunity (PHA response, anti-KLH IgG and anti-KLH IgM) was not significantly different between voles raising large or small litters in both experiments, despite the measured difference in reproductive investment (greater litter size, litter mass, RMR and food intake in the voles raising larger litters). Total IgG was higher in voles with natural large litter size than those with natural small litter size, but decreased in the enlarged litter size group compared with control and reduced group. Our results showed that immune function is not suppressed to compensate the high energy demands during lactation in Brandt's voles and contrasting the situation in birds, is unlikely to be an important aspect mediating the trade-off between reproduction and survival.  相似文献   

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