ObjectiveTo investigate the effect of immunoglobulin G (IgG) extravasated from blood circulation on the expression of toll-like receptor 4 (TLR4) induced by peripheral lipopolysaccharide (LPS) in rat brain. Methods The rats were divided into four groups in random, 5 rats in each. Group one received LPS 100μg/kg by intraperitoneal administration, normal saline was given by intravenous injection 6 hours later; group two was injected with adrenalin (AD) 15μg/kg intravenously; group three was treated with LPS intraperitoneally, AD was injected 6 hours later; group four was injected normal saline intravenously as control. For all groups, the animals were sacrificed 30 min after the last injection, and the brains were taken for investigation of the TLR4 expressions by immunofluorescence staining and RT-PCR. Result Immunofluorescence staining showed that IgG immunoreactive product was patch-like, distributed in the brain parenchyma in all the animals that received AD. In the LPS+normal saline group, IgG was found merely around the blood vessels. Meanwhile, in LPS+AD animals, TLR4 immunoreactive product coexisted with microglia marker Iba-1 within the IgG extravasated area. The double-labeled cells dispersed in the brain parenchyma and near to the cerebral vessels. In the LPS+saline group, TLR4 positive cells were endothelial-like. RT-PCR results indicated that the expression level of TLR4 in the LPS+AD group were significantly higher than that in the LPS+saline group or AD group or the saline control (P<0.01). Conclusion Extravasated circulating IgG may enhance the TLR4 expression in the rat brain induced by peripheral LPS.

Objective To study the expressions of IL-1 receptor type Ⅰ(IL-1RI) mRNA and IL-1? protein in the rat carotid body. Methods In situ hybridization,immunofluorescence double staining and Western blotting methods were used. Results The result of in situ hybridization showed that the positive signal of IL-1? mRNA was mainly located in the glomus cells of the carotid body.The result of immunofluorescence double staining showed that IL-1? protein also expressed in the glomus cells of the organ.The Western blotting proved that the IL-1? immunoreactive band appeared at 18kD,consistent with the molecular weight of the cytokine.Conclusion The glomus cells of the rat carotid body not only express IL-1RI mRNA,but also IL-1?.

Fractalkine has been recognized as the first member of the fourth chemokine family recently and its receptor, CX3CR1, was identified afterwards. This pair of ligand/receptor play important roles in the migration and adhesion of peripheral leukocyte through different ways. They are also likely to be related to the embryogenesis and regeneration of several organs and may possess some functions in the central nervous system.

Fractalkine has been recognized as the first member of the fourth chemokine family recently and its receptor, CX3CR1, was identified afterwards. This pair of ligand/receptor play important roles in the migration and adhesion of peripheral leukocyte through different ways. They are also likely to be related to the embryogenesis and regeneration of several organs and may possess some functions in the central nervous system.

Objective To investigate the effect of stress induced by water restriction on the level of phosphorylated(ERK1/2) in rat brain. Methods Fifty-eight male Wistar rats were used and randomly divided into control group(C,n=4) and three experimental groups: TW(drinking at scheduled time),EB(empty bottle stimulus),WR(restricted water drinking),which were subdivided into three subgroups by time as 3d,7d, 14d(n=6 for each).In C group,water was freely accessed to the animal for one week.In the experimental groups the water supply was restricted following a week of accommodation and the other week for timed water supply training.In TW group,the water was supplied twice a day and 10 min for each in a fixed time. In EB and WR groups,the water was served only once a day for 10 min,and in the other scheduled time for water supply only an empty bottle without water was provided in the EB group and water was limited in the WR group.All the animals were deeply anesthetized 1h after the last stimulus and transcardially infused,then the brains were cut into free-floating sections and processed for immunohistochemical staining of pERKI/2 with ABC method.The expression of pERK1/2 positive staining was measured with image analysis system. Results The area of phosphorylated ERK1/2 was significantly increased in many brain structures,especially in paraventricular hypothalamic nucleus(PVN),supraoptic nucleus(SON),ventrolateral septum(LSV),medial amygdaloid nucleus(MeA),central amygdaloid nucleus(CEA) and nucleus of solitary tract(NTS) in TW,EB and WR group compared with C group.The expression of phosphorylated ERK1/2 in SON,LSV, MeA and CeA in EB and WR group were higher than that in TW group;pERK1/2 expression of LSV,MeA,CeA and NTS in EB group increased and went down more early and quickly than that in WR group.The response of phosphorylated ERK1/2 was dependent on both stimulus methods and time in all the nuclei mentioned above except PVN,in which only the stimulus time was related. Conclusion The level of pERK 1/2 was significantly altered in PVN,SON,LSV,MeA,CeA and NTS following stimulation of water restriction.The results indicate that the activated nuclei in the brain by physical and psychological stressors are different.

The cortical distribution of thecells of origin of the corticotrigeminal projection to the oral subnucleus of spinal trigeminal nucleus(Vo)was examined with the HRP retrograde tracing method. The results showed that the coronal gyrus was the main site of origin. The anterior part and the posterior part of the gyrus projected to the dorsomedial portion and the ventrolateral portion of Vo respectively. The amount of labelled cells in the anterior part of the gyrus was much larger than those in the posterior. There were also numerous labelled cells in the anterior parts of orbital gyrus and of the lateral zone of anterior sigmoid gyrus. The most anterior ends of these three gyri joined together forming the so-called "presylvian gyrus" where the labelled cells were most concentrated. In addition, the labelled cells were also scattered in the anterior suprasylvian gyrus, posterior sigmoid gyrus, lateral gyrus and anterior ectosylvian gyrus. All labelled cells were located in the fifth layer of the cortex. Their size varied. The results of the present study did not support that there were projections from the temporal and occipital lobes and proreate gyrus to Vo.

Objective To establish the role of hypothalamic neuroendocrine nuclei in neuroimmunomodulation,peripheral immune challenge\|linduced changes of immune cytokine receptor expression in hypothalamic paraventricular nucleus(PVN) and supraotic nucleus(SON) were studied. Methods Following LPS or SEB was administered intraperitoneally,the expression of proliferating cell nuclear antigen(PCNA) of splenic cells and IL\|1 receptor type Ⅰ in PVN and SON were observed by using immunocytochemistry.Double fluorescent labeling technique was used to determine the relationship of IL\|1 receptor type Ⅰ co\|expressions with arginine vasopressin or oxytocin. Results 1.Compared with the controls,the expression of PCNA of mouse splenic cells was significantly enhanced by LPS or SEB ( P