Effects of Taishan Robinia pseudoacacia Polysaccharides on immune function in chickens

To determine the immune function of Taishan Robinia pseudoacacia Polysaccharide (TRPPS) on chickens, 240 chickens were selected as experimental animals and treated with various doses of TRPPS by hypodermic injection before immunized NDV inactivated vaccine. The results indicated that any dose of TRPPS could significantly promote the development of the immune organs, increase the quantity of leukocyte and the ratio of lymphocyte, and improve the antibody titers against Newcastle disease. Meanwhile, it also increased the magnitude of SIgA in duodenum. However, the dose of 200 mg/ml showed to be the most effective. Therefore, in terms of improving immunologic function and production performance, TRPPS could be used as a vaccine immunopotentiator for immune responses.     

Effects of gestational and lactational exposure to low doses of PCBs 126 and 153 on anterior pituitary and gonadal hormones and on puberty in female goats

The aim of the present study was to investigate if environmental doses of PCB 153 and PCB 126 could produce effects in a controlled animal model. Possible adverse effects on the hypothalamic-pitutitary-gonadal axis were examined by measuring gonadotrophins and gonadal steroid hormone concentrations in goat kids exposed during gestation and lactation. The concentrations of PCB 153 and PCB 126 in adipose tissue in the goat kids 9 months post-partum were 5800 ng/g (fat-weight, range; 2900-12700 ng/g) and 0.49 ng/g (fat-weight, range; 0.28-0.80 ng/g), respectively. The pre- and post-pubertal plasma concentrations of luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (Prl) and progesterone (P4) were analysed. LH, FSH, Prl, and P4 were also measured during an induced oestrus cycle. The prepubertal LH concentration was significantly lower, the puberty was delayed and the P4 level during the luteal phase of an estrous cycle was higher in the group exposed to PCB 153. No significant effect of PCB 153 exposure was found on Prl and FSH. PCB 126 did not produce any effects at the exposure level tested in this study. In conclusion, perinatal exposure to PCB 153 affected the reproductive function and the puberty maturation in goats.     

Effects of acute exposure to PCBs 126 and 153 on anterior pituitary and thyroid hormones and FSH isoforms in adult Sprague Dawley male rats.

3,3'4,4',5-Pentachlorobiphenyl (PCB 126) and 2,2',4,4',5,5'-hexachlorobiphenyl (PCB 153) were administered to adult male rats in order to identify sensitive indicators of endocrine disruption. We tested the hypothesis that PCB exposure modifies follicle-stimulating hormone (FSH) pituitary isoforms, as well as the pituitary and serum concentrations of FSH, luteinizing hormone (LH), growth hormone, prolactin, and thyroid-stimulating hormone (TSH). Effects on serum levels of thyroxine (T4) and testosterone (T), and prostate androgen receptor content, were also tested. In one experiment, 5 groups of 8 rats each received two i.p. injections, one day apart, of either corn oil or 6.25, 25, 100 or 400 micrograms/kg/day of PCB 126. Decreases (p < 0.05) in the serum concentrations of T4 and LH started at doses of 25 and 100 micrograms/kg/day, respectively. Serum FSH concentrations were reduced (p = 0.07) in the highest dose group. In contrast, pituitary content of FSH and LH increased with PCB-126 doses (p = 0.004, p = 0.002, respectively). Despite changes in reproductive hormones, PCB-126 had no effect on the androgen receptor content of the prostate. The effect of PCB-126 was tested in the hemicastrated rat, and suggested adverse effects on testosterone secretion. To test the effects of PCB exposure on FSH pituitary isoforms, 4 groups of 10 male rats received two i.p. injections, one day apart, of either corn oil, PCB 153 (25 mg/kg/day), estradiol-17 beta (E2; 20 micrograms/kg/day), or PCB 126 (0.1 mg/kg/day). Serum T4 levels were higher (p < 0.01) in the E2 and PCB 153 groups, and slightly reduced in the PCB 126-treated groups, compared to controls. Simultaneous purification of pituitary FSH and TSH isoforms was performed by HPLC, using two chromatofocusing columns in series. In contrast to TSH isoforms, the distribution of FSH isoforms over the chromatography run differed slightly between treatment groups; the amounts of FSH isoform eluted during the pH gradient were lower (p < 0.05) in E2 and PCB 153-treated rats than in control or PCB 126-treated rats. The similarity between the effects of E2 and PCB 153 on T4 and FSH isoforms supports the contention that PCB 153 possesses estrogenic properties. Serum LH and T4 concentrations were the most sensitive and practical endocrine indicators of PCBs 126 and 153 exposure in male rats.     

Effects of exposure to PCBs and related compounds on growth and activity in children

Two hundred thirty-six children from two established cohorts at risk for exposure to polychlorinated biphenyls (PCBs) and related contaminants were evaluated at age 4 years. Prenatal exposure (assessed by cord serum PCB level) was associated with lower weight, an effect consistent with reports of growth retardation in laboratory rats and in children exposed at high levels in Taiwan and at general population levels in Japan. The highest exposed children weighed 1.8 kg less on the average than the least exposed. Contemporary body burden (assessed by 4-year serum PCB level) was associated with reduced activity based on composite ratings provided by the child's mother and two independent examiners. This effect, attributable to lactation exposure, was strongest among the offspring of women with above average milk PCB levels who breast fed for at least 1 year. While the weight deficit is consistent with previous data linking developmental effects of low-dose human PCB exposures specifically to the prenatal period, activity is the first domain found to be affected by lactation at contemporary levels of exposure.     

抗肿瘤药物对职业接触护士免疫功能的影响

目的:探讨职业接触抗肿瘤药物对护士免疫功能的影响。方法:选择接触抗肿瘤药物5年以上,每日接触5人次以上护士为接触组;无抗肿瘤药物接触史的健康志愿者为对照组。抽取接触组及正常对照组外周静脉血各3mL,EDTA抗凝血各2mL,利用我院血清免疫球蛋白常规检测方法及流式细胞仪技术观察血清免疫球蛋白及外周血T淋巴细胞亚群的变化。结果:血清免疫球蛋白IgG接触组较正常对照组减少,差异具有显著性(P<0.05);血清免疫球蛋白IgM、IgA接触组与对照组比较,差异无显著性(P<0.05);接触组T淋巴细胞亚群CD4+细胞下降,与对照组比较差异具有显著性(P<0.05)。CD8+有上升趋势,CD4+/CD8+比值有下降趋势,两组比较无显著性差异;CD3+及NK细胞接触组与对照组比较也无显著性差异(P>0.05)。结论:职业接触抗肿瘤药物可能减低护士的体液免疫功能。     

角鲨烯作为新型佐剂的免疫效果研究

目的研究以角鲨烯作为新型佐剂制备的新城疫、禽流感H5N1和H9灭活疫苗在SPF鸡体内的抗体效价水平以及对机体的细胞免疫作用。方法本试验油相中按一定的比例添加角鲨烯,按照常规方法制备灭活疫苗,免疫SPF鸡后,采用微量血凝抑制法和MTT法分别检测了SPF鸡免疫不同疫苗后机体的抗体效价水平和机体外周血T淋巴细胞的动态增殖变化。结果免疫以角鲨烯作为新型佐剂制备的新城疫、禽流感H5N1和H9灭活疫苗后,HI抗体在免疫后第2周检测为阳性,第3周达到最大值,持续到第4周抗体效价无明显下降(P>0.05);免疫组外周血T淋巴细胞增殖显著高于对照组。结论表明以角鲨烯作为新型佐剂制备的新城疫、禽流感H5N1和H9灭活疫苗对SPF鸡的促抗体效价作用和细胞免疫作用均有显著增强。     

Effects of in ovo and acute diazepam treatments on peripheral benzodiazepine receptors and cutaneous basophil hypersensitivity in chickens

Prenatal diazepam treatment impairs immune responses in mammals, but chicken embryos allow experimental manipulation isolated from maternal influences on embryo development. In ovodiazepam treatment in chickens decreased macrophage spreading and phagocytosis. In the present experiment, we investigated the effects of in ovoand/or acute diazepam treatments on phytohemagglutinin (PHA)-induced cutaneous basophil hypersensitivity (CBH) response in chickens. Forty day-old chickens, treated in ovo with 8 mg diazepam/kg, 2 ml diazepam vehicle/kg, or sham-manipulated. were subsequently treated po with 2 mg diazepam/kg or with diazepam's vehicle 1 h before PHA injection. The existence of an interaction between diazepam treatments was shown. Birds acutely treated with diazepam exhibited an increment in CBH response. In contrast, in ovo diazepam treatment per se did no change animals' response to PHA, but antagonized acute diazepam effects on CBH response. The results occurred through direct and/or indirect action of diazepam on cytokine and/or glucocorticoid hormone production and release. In the former case, the effects might be related to stimulation of peripheral benzodiazepine receptors (PBR) on immune cells, thus changing the cytokine cascade, while in the latter instance they might be mediated through glucocorticoid hormones via PBR stimulation in the adrenal gland cells.     

小鼠孕期染镉对子代免疫功能的影响

小鼠在受孕第９～１５天给予氯化镉灌胃，剂量分别为０，１．０，１０．０ｍｇ／ｋｇ，检测其仔鼠在４和８周龄对各项免疫功能的变化。结果发现，从时间上来看，仔鼠外周血白细胞总数、Ｔ淋巴细胞计数和血清溶血素滴度在８周龄时低剂量组有刺激作用，在４周龄时均无影响，表现出迟发作用；从剂量上看，８周龄时上述指标均为低剂量有刺激作用，高剂量无影响。而血清溶菌酶是在４周龄时高剂量组有抑制趋势。母鼠产后２１天肝肾内有明显的镉蓄积，仔鼠胸腺、脾、肝、肾中却未见明显镉蓄积，说明镉对仔鼠免疫功能的影响不是直接作用所致     

Effects of fenthion, fenitrothion and desbromoleptophos on gait, acetylcholinesterase, and neurotoxic esterase in young chicks after in ovo exposure

Previous studies have demonstrated that gait is affected in chicks exposed to organophosphorus esters (OPs) that induce delayed neurotoxicity (OPIDN) in adult hens. To investigate the developmental relationship between such functional deficits and OPIDN, chicks were exposed to 3 OPs with different OPIDN potential. Desbromoleptophos (DBL) induces OPIDN in adult hens; fenthion (FEN) has uncertain OPIDN potential; fenitrothion (FTR) does not induce OPIDN. Chicks were treated by injection into the egg on day 15 of incubation, after the presumed period of OP-induced structural teratogenesis. AChE and neurotoxic esterase (NTE) were assayed during incubation and in parallel with post-hatching evaluations of gait. DBL, 125 mg/kg in ovo, caused paralysis in 70% of chicks after hatching. The gait of surviving chicks was affected for at least 6 weeks and marked by toes curling under. NTE was inhibited until 10 days post-hatching and AChE until hatching. FEN did not inhibit NTE significantly, but AChE was significantly inhibited until hatching. Chicks exposed as embryos to FEN were hyperactive and aggressive. Gait was still affected 6 weeks after treatment with 3 mg/kg FEN. FTR at 125 mg/kg inhibited AChE until day 10 post-hatching, but neither inhibited NTE nor affected gait. The growth of OP-exposed chicks was not significantly decreased, so the decreased length and increased width of the stride could not be ascribed to stunted growth. We conclude that OPs cause irreversible effects on gait that are not related to their defined neurotoxic effects, since altered gait (1) occurs below the age of sensitivity to OPIDN, (2) is seen in the absence of NTE inhibition and (3) does not invariably accompany AChE inhibition.     

Effects of PCB 126 on primary immune organ development in chicken embryos

This experiment evaluated the immunotoxic effects of developmental exposure to a planar polychlorinated biphenyl (3,3',4,4',5-pentachlorobiphenyl; PCB 126) in chicken embryos. Previous investigations on the immunotoxic effects of PCBs and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in developing avian embryos were undertaken with embryos exposed only during the latter stages of incubation. To simulate exposure in embryos in the wild, chicken eggs were injected with PCB 126 (sunflower oil carrier) into the air cell before initiation of incubation. It was hypothesized that exposure to PCB 126 during the complete incubation period would decrease immune organ masses and lymphocyte numbers. Doses of PCB 126 ranged from 0.051 to 0.80 ng/g egg. Control groups consisted of carrier-injected and noninjected eggs. The thymus and bursa of Fabricius were removed and weighed on d 20 of incubation (1 d before hatch). The immune organs were homogenized, and viable lymphoid cells were counted using the trypan blue exclusion method. Probit analysis estimated the LD20 to be 0.21 ng/g and the LD50 to be 1.01 ng/g. Thymus mass dropped sharply between 0.13 and 0.32 ng/g, and lymphoid cell numbers in the thymus fell sharply between 0.051 and 0.13 ng/g. Bursa mass began to decrease at the lowest dose of 0.051 ng/g and reached a minimum at 0.32 ng/g. The number of viable cells decreased slightly at 0.051 ng/g and reached a minimum at the 0.13- and 0.32-ng/g doses. In general, lymphoid cell numbers were more sensitive to PCB 126 than organ masses, and the bursa tended to be more sensitive than the thymus. Doses necessary to reduce the number of viable lymphoid cells in the thymus and bursa were at least one order of magnitude lower with full-term incubation as compared to exposure only during later stages of incubation.     

Embryonic exposure to lead: comparison of immune and cellular responses in unchallenged and virally stressed chickens

Lead, a ubiquitous environmental contaminant, has been shown to modulate various functions of the immune system and decrease host resistance to infectious disease. However, limited information is available concerning the direct effects of lead on the host immune response to an infectious agent after developmental exposure. The current study utilized chickens to examine the effect of embryonic lead exposure on immune and cellular responses during viral challenge. Sublethal doses of lead were introduced into fertilized Cornell K Strain White Leghorn chicken eggs via the air sac at day 5 or day 12 of embryonic development (designated as E5 and E12, respectively). Four-week-old female chickens were inoculated with infectious bronchitis virus (IBV) strain M41. Antibody titer to IBV, delayed-type hypersensitivity (DTH) response against bovine serum albumin (BSA), the absolute number and percentage of leukocyte subpopulations, and interferon-gamma (IFN-gamma)-like cytokine production by splenocytes were evaluated at 5-6 weeks of age. While antibody response to IBV in juvenile chicks was unaffected by the in ovo lead exposure, IFN-gamma-like cytokine production by splenocytes was significantly depressed following lead exposure at both developmental stages. In contrast with this pattern, the DTH response against BSA was unaffected following E5 exposure, but was significantly decreased after E12 exposure to lead. These changes were similar to those previously reported in chickens not exposed to IBV. While lead exposure at E5 induced significant changes in the percentage of circulating heterophils at 1 day postinfection (dpi), lead did not cause any change in relative leukocyte counts after E12 exposure. At 7 dpi, E5 lead exposure resulted in decreased absolute number and percentage of circulating lymphocytes, while total leukocyte counts, and the absolute number and percentage of circulating monocytes and heterophils were significantly reduced in E12 lead-exposed chickens. These results suggest that low-level exposure to lead has a direct effect on the developing chicken immune system, which is evident even during a postnatal infection. Furthermore, some of the changes were observed only when chicks were stressed by the viral infection. It appears that lead exposure during different stages of embryonic development is likely to result in different immunotoxic outcomes in juveniles.     

Effects of PCB 126 on primary immune organs and thymocyte apoptosis in chicken embryos

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and polychlorinated biphenyl (PCB) 126 produce thymic atrophy and immunosuppression. This study explored the hypothesis that the thymic atrophy produced by developmental exposure to PCB 126 is associated with an increase in apoptotic thymocytes at the end of incubation in chicken embryos. Eggs were injected via the air cell with PCB 126 (0.05, 0.13, 0.32, 0.64, and 0.80 ng/g egg) on d 0 of incubation, and tissues were collected on d 20. Controls included noninjected and vehicle-injected (sunflower oil) eggs. Thymocytes were cultured for 6 h and analyzed by flow cytometry for decreased DNA content (propidium iodide staining) and cell size (forward scatter), which indicate apoptosis. PCB 126 induced dose-dependent mortality with an LD50 of 1.01 ng/g and lowest-observed-effect concentration (LOEC) of 0.32 ng/g. Teratogenic effects commonly associated with TCDD and planar PCBs, including cranial and foot deformities and subcutaneous edema, tended to increase with dose of PCB 126. PCB 126 reduced thymus mass by approximately 20% at 0.64 and 0.8 ng/g, the number of viable thymocytes by approximately 20-24% at and above 0.13 ng/g, and the number of bursal lymphoid cells by 57% at 0.64 ng/g. The percentage of apoptotic thymocytes increased with dose, reaching levels 2 times greater than controls at 0.8 ng/g. Electrophoresis of low-molecular-weight DNA from thymocytes of all doses demonstrated fragments in multiples of 180 bp. This DNA laddering is a hallmark of apoptosis. At all doses, thymocytes exhibited caspase-3 activation, another indicator of apoptosis. The results of this experiment supported the hypothesis that the thymic atrophy produced by developmental exposure to PCB 126 in chicken embryos is associated with an increase in apoptotic thymocytes on embryonic d 20.     

Effects of furazolidone, PCB77, PCB126, Aroclor 1248, paraquat and p,p'-DDE on transketolase activity in embryonal chicken brain

The effect of in ovo exposure to PCBs, DDE and paraquat on transketolase activity was measured in 19-day-old chicken embryos. Furazolidone was used as a positive control for decreased activity of the enzyme. The potency of contaminants to interact with transketolase was also tested in an in vitro system, using control brain 7000xg supernatants containing the enzyme. No effects were found on transketolase activity after in ovo or in vitro exposure to PCB126, Aroclor, DDE or paraquat. PCB77 decreased transketolase activity in vitro, but only at concentrations that, extrapolated to in ovo exposure, would be lethal to the embryo. Furazolidone decreased transketolase activity both in ovo and in vitro. For this contaminant, thiamine residues were analysed in the yolk sacs, but no differences were found between exposed and non-exposed eggs. Transketolase is dependent on thiamine pyrophosphate as a cofactor, and therefore, the decreased enzyme activity could be the result of an interaction between furazolidone and thiamine metabolism. Since thiamine residues were not affected by furazolidone and transketolase inhibition in vitro was similar to the inhibition after in ovo exposure, it was concluded that furazolidone interacted with transketolase on the enzymatic level rather than by a depletion of thiamine.     

Adverse effects of fipronil on avian reproduction and development: maternal transfer of fipronil to eggs in zebra finch Taeniopygia guttata and in ovo exposure in chickens Gallus domesticus

Two studies were carried out to examine the impact of maternal fipronil exposure on embryonic and offspring development. In the first study, breeding female zebra finches were orally dosed with single sublethal levels of fipronil (1, 5, and 10 mg/kg body weight) to determine behavioural and developmental consequences on chicks following maternal pesticide exposure. Significant levels of fipronil and fipronil-sulfone residues were detected in eggs laid by females in all dosed groups, however, these were undetectable in eggs laid 13 days after treatment. The level of sulfone detected in eggs was consistently higher than that of the parent fipronil compound. Of the seven eggs laid in the treatment groups, only one (14%) chick hatched and this was from the lowest dose group. This chick was severely underdeveloped at 10 days of age in comparison to control chicks and fiproles were detected in brain, liver, and adipose tissues collected following euthanasia of this individual. In contrast, there was 100% hatchability of control group eggs and all chicks fledged nests on schedule. In the second study, domestic chicken eggs were injected with 5.5, 17.5, and 37.5 mg/kg egg weight of fipronil directly into the yolk sac on day 12 of incubation. Treatment did not affect hatching success, however, behavioural and developmental abnormalities were observed in hatchlings from the highest dose group. These chicks also demonstrated reduced feeding rates, as indicated by reduced body mass at 48 h period post hatch. Both fipronil and fipronil-sulfone residues were detected in brain and liver tissue of hatchlings at all pesticide dose levels tested.     

Effects of O,S,S-trimethyl phosphorodithioate on immune function

The effect of acute administration of 20-80 mg/kg O,S,S-trimethyl phosphorodithioate (OSS-TMP) to C57BL/6 female mice on the murine immune system was determined. The parameters examined to evaluate overt toxicity of the compound included body weight, plasma cholinesterase levels, splenic nucleated cell number and thymic weight and nucleated cell number. Acute administration of 60 or 80 mg/kg OSS-TMP led to a 75 or 63% decrease, respectively, in plasma cholinesterase levels and a decrease in thymic size. At a dose of 80 mg/kg OSS-TMP, the animals also exhibited some lethargy and body weight loss. Below 60 mg/kg OSS-TMP, no overt toxic manifestations were observed. These studies were carried further to determine the effect of OSS-TMP on the generation of in vivo primary and in vitro secondary cellular and humoral immune responses. At nontoxic doses of the compound, i.e. 20 and 40 mg/kg OSS-TMP, the in vivo generation of a primary cytotoxic T lymphocyte (CTL) response to alloantigen was significantly elevated, but this response was unaffected following restimulation of the splenocytes by alloantigen in vitro. The generation of an in vivo primary and in vitro secondary humoral responses to sheep red blood cells (SRBC) was elevated following a single dose of 40 mg/kg OSS-TMP. Administration of toxic doses of OSS-TMP, i.e. 60 and 80 mg/kg, did not alter the ability of splenocytes to generate a primary or secondary CTL response, but suppressed the generation of humoral immune responses. These results differ significantly from those observed in a similar system following acute administration of a structural analog, O,O,S-trimethyl phosphorothioate which was previously shown to have potent immunosuppressive activity at nontoxic doses.     

Effects of embryonic exposure to ethanol on zebrafish visual function

Across a variety of species, including humans, it has been shown that embryos exposed to ethanol display eye abnormalities as well as deficiencies in visual physiology and behavior. The purpose of this study was to examine the effects of embryonic exposure to ethanol on visual function in zebrafish. Visual function was assessed physiologically, via electroretinogram (ERG) recordings, and behaviorally, by measuring visual acuity with the optomotor response. Zebrafish larvae were exposed to 1.5% ethanol at various times during development, including the period of maximal eye development. The results show that ethanol effects on visual function were most pronounced when exposure occurred during eye development. ERG recordings from ethanol-exposed larvae differed from normal subjects both in shape of the response waveform and in visual thresholds under both light and dark adaptation; the differences were more pronounced under lower levels of adaptation. Also, ethanol-exposed larvae displayed lower visual acuity as determined from the optomotor response. These results indicate embryonic ethanol exposure affects visual function particularly when exposure occurs during eye development. In addition, these findings illustrate the usefulness of the zebrafish as a viable animal model for studying Fetal Alcohol Syndrome (FAS).     

Effects of oral exposure to trichloroethylene on female reproductive function

The present study was conducted to determine if subchronic oral exposure to trichloroethylene (TCE) influenced female reproductive performance, and if TCE or major metabolites trichloroacetic acid (TCA) and trichloroethanol (TCOH) preferentially accumulated in female reproductive organs or neonatal tissues. Female Long-Evans hooded rats were exposed to vehicle (corn-oil), 10, 100 or 1000 mg/kg/day by gavage for 2 weeks before mating and throughout mating to day 21 of pregnancy. Gas chromatography analysis of tissues from females at the end of premating exposure indicated that TCE levels were uniformly high in fat, adrenals and ovaries across treatment groups, while uterine tissue had relatively high levels of TCA. Female fertility, however, was not influenced in any treatment group. In the 1000 mg/kg/day group, 5 out of 23 females died and weight gain was significantly depressed throughout the treatment period. Neonatal survival was significantly depressed in this group alone, with the majority of deaths occurring among female offspring at the time of birth. TCA levels in blood, liver, and milk contents of the stomach in female but not male neonates increased across treatment groups. These results indicate that oral exposure to TCE at levels below those causing limiting maternal toxicity had no influence on pregnancy outcome, and that the accumulation of TCE and TCA in ovaries, adrenals and uteri had no influence on mating success.     

青蒿琥酯对小鼠免疫功能的影响(英文)

目的:研究青蒿琥酯对小鼠免疫功能的影响. 方法:溶血素含量用分光光度法测定,血清IgG和C3含量用单向免疫扩散法测定,淋巴细胞转化率、巨噬细胞吞噬百分率和吞噬指数镜检计数.结果:青蒿琥酯im 75 mg kg~(-1) bidfor 5—7d能降低SRBC致敏小鼠血清溶血素和IgG的含量,抑制抗体生成,但增加疟鼠补体C3的含量.青蒿琥酯能促进PHA诱导的小鼠体内淋巴细胞转化,能提高DNFB所致的迟发型超敏反应,并减少腹腔巨噬细胞的吞噬百分率和吞噬指数.结论:青蒿琥酯对体液免疫有抑制作用,但对细胞免疫有促进作用.     

木犀草素对炎症和免疫功能的影响

木犀草素(Lut)是白毛夏枯草的有效成分。对多种动物的急慢性炎症模型均有明显抑制作用。对Schultz-Dale反应有抑制作用。对SRS-A和组织胺引起的回肠收缩,分别呈现竞争和非竞争性拮抗。Lut还可提高豚鼠过敏性脑脊髓炎的发病率,促进免疫低下小鼠的抗体形成,和增强静止或由亚适浓度PHA激活的淋巴细胞增殖。Lut的抗炎、抗速发型超敏反应和免疫增强作用,可能是其治疗慢性气管炎具有良效的药理基础,