异丙酚对家兔全脑缺血再灌注损伤的影响

目的：观察异丙酚对家兔全脑缺血再灌流（I/R）损伤的保护作用,探讨其作用机制。方法：24只家兔随机分为A、B和C组,每组8只,C组缺血30min再灌流4h,缺血前静注异丙酚5mg·kg^-1,随后输注异丙酚20mg·（kg·h）^-1直至实验结束;B组为单纯I/R组,A组仅分离血管不阻断。分别在缺血前15min（I0）及再灌流30min（R1）、2h（R2）和4h（R3）取颈内静脉血,测定血浆ET-1、MDA和SOD的含量,实验结束取皮层HE染色,光镜观察,并测量神经原核截面积。结果：①C组ET-1随再灌流时间延长缓慢增加,在R3时仅增加2倍,但较B组相应值显著降低（P〈0.05）;而B组成倍增加,至R3时增加4.9倍（P〈0.01）;②MDA在C组R1-R3无明显变化,较B组相应时点降低（P〈0.05）,而B组R1-R3较I0及A组各时点升高（P〈0.01）。SOD在C组R1-R3较B组同期明显增加;③C组核截面积比B组显著增加（172.28μm2vs105.63μm2,P〈0.05）;④光镜下C组皮层轻度水肿、核固缩较少,而B组皮层水肿明显,大量神经元坏死。结论：异丙酚通过增强机体抗氧化能力,抑制ET-1的合成和释放,阻断氧自由基和ET-1之间的恶性循环,从而保护脑I/R损伤。     

Protective effect of spermine on rats with acute cerebral ischemia/reperfusion injury

AIM: To study the effects and the possible mechanisms of exogenous spermine on the rats with acute transient focal cerebral ischemia/reperfusion (I/R) injury.METHODS: The rat model of focal cerebral ischemia/reperfusion was established by middle cerebral artery occlusion (2 h) and reperfusion (2 h). Healthy adult SD rats were divided into 5 groups;sham group,I/R group and spermine(4,20 and 40 mmol/L)groups.The degree of cerebral injury was evaluated by neurological deficit score, infracted volume, superoxide dismutase (SOD) activity and malondialdehyde (MDA) content. The morphological changes of the brain were observed by HE staining and electron microscopy. RESULTS: Compared with I/R group, the neurological deficit score, infracted volume and the content of MDA were decreased, the SOD activity was increased and the ultrastructural changes were improved in spermine-treated groups. CONCLUSION: Exogenous spermine has a protective effect against acute focal cerebral ischemia/reperfusion injury. The mechanisms may be related to scavenging free radical by spermine.     

Stability of cerebral focal ischemia/reperfusion model induced by monofilament in Kunming mice

AIM: To study the stability of mouse cerebral ischemia/reperfusion model induced by the method of monofilament. METHODS: Sixty male Kunming mice were divided into 3 groups according to the body weight: group A (18-21 g), group B (22-28 g) and group C (30-35 g). Ischemia/reperfusion (I/R) model was made by middle cerebral artery occlusion (MCAO) with nylon monofilament. To evaluate the mouse MCAO model, the method of PRM2 laser Doppler was used to detect the cerebral blood flow, the neurological deficit scores were determined by Longa standard and infarction volume was detected with TTC staining. The content of malondialdehyde (MDA) and activity of superoxide dismutase (SOD) were also measured by ELISA. RESULTS: The successful rates of model establishment in both group A and group B were higher than that in group C (P＜0.05), especially the highest in group B . The mortality in group A was significantly higher than that in group B and group C (P＜0.05). The behavior scores and cerebral infarct volume in group A and group B were significantly higher than those in group C (P＜0.05). Obvious brain injury and neurological deficits were also observed in group A and group B with the higher content of MDA and the lower activity of SOD in the cerebral cortex of the injury side. CONCLUSION: There are three important factors to ensure the success and stability of MCAO mouse model induced by monofilament, i.e. the diameter of monofilament matching the body weight of the mice, the suitable length of monofilament within the blood vessel, as well as the maintaining of proper room temperature during experiment. The MDA content and SOD activity are also effective indexes for evaluating the cerebral I/R injury.     

Propofol inhibits activation of p38 MAPK in rat brain tissues with LPS-induced brain injury

AIM: To investigate the effects of propofol on lipopolysaccharide (LPS)-induced activation of p38 mitogen-activated protein kinase (p38 MAPK) and inducible nitric oxide synthase (iNOS) in brain tissues of rats. METHODS: Sprague-Dawley rats of both sexes were randomly divided into 3 groups (n=24 each): control group, LPS group and LPS+propofol group. The models of LPS-induced brain injury were established by injecting LPS (1 mg/kg) via left internal carotid artery in LPS group. Propofol (100 mg/kg) was given intraperitoneally immediately after the LPS was given in LPS+propofol group. The same volume of normal saline was given to the rats in control group. The rats were decapitated 6 h, 24 h, 48 h and 72 h after administration. The brains were immediately isolated to detect the water content, activation of p38 MAPK and the exepression of iNOS protein. Meanwhile, the pathological changes were observed under light microscope. RESULTS: The water content of the brain was higher in LPS group than that in control group. The protein levels of phosphorylated p38 MAPK(p-p38 MAPK) and iNOS in LPS group increased 6 h after LPS administration, reached the peak at 24 h, and still higher than those in control group at 48 h and 72 h (P<0.05). The levels of those indexes were all lower in LPS+propofol group at various time points than those in corresponding LPS group (P<0.05). The pathological changes were slighter than those in LPS group. The water content of the brain was positively correlated with the levels of p-p38 MAPK and iNOS (r=0.603, r=0.727,P<0.05). CONCLUSION: Propofol attenuates LPS-induced brain injury by inhibiting the activation of p38 MAPK and down-regulating iNOS expression.     

Protective effects of garlic (Allium sativum) extract upon lindane-induced oxidative stress and related damages in testes and brain of male rats

The purpose of this study, carried out on male Wistar rats, was to evaluate the beneficial effects of garlic (Allium sativum) extract injections upon lindane-induced damages in testes, brain and thyroid function. Under our experimental conditions, lindane poisoning (in drinking water for 30 days, supplying about 50 mg/kg body weight per day) resulted in a decreased weight of testes, epididymides, prostate gland and seminal vesicles (−52%, −42%, −50% and −5%, respectively), a decrease of spermatozoa count and motility (−56%, −37%, respectively), an increased level of free thyroxin (+84%) and decreased levels of TSH and FSH in serum (−74%, −77%, respectively). In addition, lindane treatment triggered an oxidative stress in testes and brain as revealed by an increased level of lipids peroxidation (TBARS) (+96%,+92%), an increase of superoxide-dismutase activity in testes (+69%) and a decrease of glutathione-peroxidase and catalase activities in testes and brain (−52%, −34% and −49%, −45%, respectively). These lindane-induced changes were almost reversed to normal in animals injected with a garlic extract (an amount corresponding to 300 mg fresh garlic/kg/day), what confirms a beneficial effect of this vegetal source of anti-oxidants.     

高血压患者左心室肥厚与血管加压素和脑钠尿肽的关系

目的观察原发性高血压左心室肥厚与血浆血管加压素、血浆脑钠尿肽水平的关系。方法原发性高血压患者71例,采用超声心动图测算左心室质量指数后,再按照左心室质量指数分成两组:左心室肥厚组(简称肥厚组)36例,左心室非肥厚组(简称非肥厚组)35例;另设对照组28例。分别用超声心动图测定对照组左心室质量指数,以及三组舒张早期速度峰值与舒张晚期速度峰值,计算两者的比值;放射免疫分析法测定血浆血管加压素和血浆脑钠尿肽水平,并分别与左心室质量指数和舒张早晚期速度峰值的比值作直线相关分析。结果①肥厚组和非肥厚组血浆血管加压素和脑钠尿肽浓度均高于对照组(P<0.01),肥厚组血管加压素和脑钠尿肽浓度均高于非肥厚组(P均<0.01);肥厚组和非肥厚组左心室质量指数均高于对照组(P<0.01和P<0.001),肥厚组左心室质量指数较非肥厚组显著升高(P<0.001);非肥厚组和肥厚组与对照组比较,舒张早晚期速度峰值比值均减小(P均<0.01)。②血浆脑钠尿肽浓度与左心室质量指数呈显著正相关(r=0.552,P<0.01),与舒张早晚期速度峰值比值呈显著负相关(r=-0.803,P<0.01);非肥厚组血浆血管加压素与血浆脑钠尿肽呈正相关(r=0.437P<0.01)与舒张早晚期速度峰值比值呈显著负相关(r=-0.506,P<0.01)。结论①血浆血管加压素水平增加可能参与高血压患者左心室肥厚的形成,导致左心室舒张功能受损;②血浆脑钠尿肽水平可以成为判断原发性高血压患者左心室肥厚和左心舒张功能受损的一项重要指标。     

Advances in Diagnostic and Treatment Modalities for Intracranial Tumors

Intracranial neoplasia is a common clinical condition in domestic companion animals, particularly in dogs. Application of advances in standard diagnostic and therapeutic modalities together with a broad interest in the development of novel translational therapeutic strategies in dogs has resulted in clinically relevant improvements in outcome for many canine patients. This review highlights the status of current diagnostic and therapeutic approaches to intracranial neoplasia and areas of novel treatment currently in development.     

Brain injury induced by intrauterine infection affects offspring’s cognitive development and hippocampal neurogenesis

AIM: To explore the effect of brain injury induced by intrauterine infection on offspring’s cognitive development and hippocampal neurogenesis. METHODS: Sprague-Dawley pregnant rats (n=15) were randomly divided into model group (n=8) and control group (n=7). After delivery, the male pups were randomly divided into E. coligroup (n=35) and control group (n=35). Total 20 male pups at postnatal day 28 (P28) were randomly divided into 2 groups for Morris water maze test. Hippocampi of the 2 groups were used for cell apoptosis, neuronal proliferation and survival analysis. RESULTS: (1) The brain tissue was slightly atrophied in E. coligroup. The numbers of TUNEL and caspase-3 positive cells were significantly increased in E. coligroup (P<0.05). (2) In the navigation and memory task, the rats in E. coligroup had longer escape latency than that in control group (P<0.05). (3) There was a significant increase in the BrdU-labeled cells at P3, P7 and P14 in E. coligroup than that in control group (P<0.05). When the cells got mature, no significant difference of BrdU-labeled cells at P28 between the 2 groups was observed (P>0.05). CONCLUSION: Intrauterine infection increases hippocampal neuronal apoptosis, which may be regarded as an etiological factor in the cognitive development impairment. Inflammation-induced neurogenesis may play an important role in neuronal protection and repair in immature brain after intrauterine infection.     

Alterations in enzyme activities in vital organs of triploid female catfish Heteropneustes fossilis (Bloch)

Triploid Heteropneustes fossilis (Bloch) showed sterility and higher growth potential than the normal diploid fish. Activities of some metabolic enzymes such as cytosolic NADP-malate dehydrogenase (NADP-MDH), mitochondrial NAD-malate dehydrogenase (NAD-MDH) and glutamate pyruvate transaminase (GPT) were evaluated in liver, brain and kidney along with glucose-6-phosphate dehydrogenase (G-6-P D) in ovary of female triploid catfish. Activities of these enzymes showed distinct seasonal periodicity, mostly with highest activities in prespawning and spawning periods, in both diploid and triploid catfish but differed in magnitude. In triploid liver, GPT showed higher activity than the diploid counterpart in prespawning and spawning periods. On the contrary, mitochondrial NAD-MDH and cytosolic NADP-MDH in this organ showed a consistent lower activity than the diploid in all stages or in some stages of reproductive cycle respectively. Interestingly, none of the enzymes in brain and kidney of triploid female catfish showed significant changes in comparison to the diploid counterpart. The triploid ovary maintained a significantly lower level of G-6-P D activity throughout the resting, preparatory and pre-spawning periods compared to the diploid ovary. Lower level of malic enzymes (NAD-MDH and NADP-MDH) in liver and G-6-P D in ovary are in close synchrony with lower level of estradiol-17β in plasma of female triploids as found in earlier study.