Biomedical subjects

Xu Wang

Publications and source records attributed to Xu Wang.

At least 127 records · Page 7Linked to original sources

PubMed2003

Morphine enhances HIV infection of neonatal macrophages.

Perinatal transmission of HIV accounts for almost all new HIV infections in children. There is an increased risk of perinatal transmission of HIV with maternal illicit substance abuse. Little is known about neonatal immune system alteration and subsequent susceptibility to HIV infection after morphine exposure. We investigated the effects of morphine on HIV infection of neonatal monocyte-derived macrophages (MDM). Morphine significantly enhanced HIV infection of neonatal MDM. Morphine-induced HIV replication in neonatal MDM was completely suppressed by naltrexone, the opioid receptor antagonist. Morphine significantly up-regulated CCR5 receptor expression and inhibited the endogenous production of macrophage inflammatory protein-1beta in neonatal MDM. Thus, morphine, most likely through alteration of beta-chemokines and CCR5 receptor expression, enhances the susceptibility of neonatal MDM to HIV infection, and may have a cofactor role in perinatal HIV transmission and infection.

Analgesics, Opioid↗

PubMed2003

Experimental studies of the Bohm criterion in a two-ion-species plasma using laser-induced fluorescence.

The Bohm criterion is studied experimentally in the case of a two ion species plasma. Measurements are carried out in Ar and Ar+He plasmas (PA(r I) approximately 0.1 mtorr, 0< or =P(He)/P(Ar)< or =25, and 0< or =n(+)(He)/n(e)< or =0.5, T(e)< or =2 eV) created in an unmagnetized dc hot filament discharge confined by surface multidipole magnetic fields. Laser-induced fluorescence (LIF) measurements of Ar II ion velocity distribution functions (ivdfs) within the presheath up to the sheath edge show that the ions reach the sheath edge traveling faster than their individual Bohm speed by more than 75%, approaching a speed equal to the ion sound speed of the system.

Journal Article↗

PubMed2003

[Arterial switch operation in older infants with severe pulmonary hypertension].

OBJECTIVE: To investigate the clinical efficacy of arterial swith operation on transposition of great artery (TGA) and Tausing-Bing anomaly. METHODS: Between June 2000 and December 2002, 30 consecutive patients, aged 3 days to 6 years (mean, 9.4 +/- 15 months) with the mean body weight was 6.1 kg +/- 2.7 kg, underwent arterial switch operation. Among the 30 patients 7 suffered from TGA with intact ventricular septum, 19 from TGA with ventricular septal defect (VSD), 3 from Taussing-Bing anomaly, and 1 from corrected TGA; 12 were complicated by atrial septal defect (ASD) and 18 complicated by patent ductus arteriosus (PDA); 23 had severe pulmonary hypertension; 2 had left ventricular outlet stenosis. Coronary type A distribution was recognized in 26 cases, type D in 4, and one of them having the origin of the left descending artery tunneled in the aortic wall. The operation was performed under general anesthesia and extracorporeal circulation with low temperature and low volume blood flow. Prostaglandin 1 was administered pre-operatively in 3 patients, one of which underwent balloon atrial septostomy and one underwent pulmonary banding and systemic to pulmonary shunt pre-operatively. The aorta and pulmonary artery were transected above the valvular commisures, the coronary ostia with all the adjacent sinus of Valsalva were excised and re-implanted to the proximal neo-aorta, and then aortic anastomosis was completed. The proximal neo-pulmonary trunk was reconstructed with a large autologous native pericardium as a posterior patch. The pulmonary anastomosis was completed after the aortic cross-clamp was released. The VSD was repaired through the atrium or proximal aorta with dacron patches. RESULTS: Two patients died with a hospital mortality rate of 6.7%. No death was directly related to any coronary artery problem. One 5 day-old neonate with TGA and an intact septum having refractory hypotension, hypoxemia, and acidosis pre-operatively underwent a smooth emergency operation. The patient had a refractory low cardiac output syndrome post-operatively and died 20 hours after the operation. Another patient with chylothorax died of allergy from iodophor 22 days postoperatively. The pulmonary pressure decreases significantly in 22 patients who had severe pulmonary hypertension preoperatively with the mean pressure 46.7 mm Hg preoperatively and 31.3 mm Hg postoperatively. 28 patients were discharged from hospital uneventfully. Follow-up of 1 to 31 months showed survival with no late complications and death. CONCLUSION: The arterial switch procedure has a satisfying effect on TGA for patients older than 1 month with severe pulmonary hypertension.

Cardiac Surgical Procedures↗

PubMed2003

Thermodynamic characterization of the folding coupled DNA binding by the monomeric transcription activator GCN4 peptide.

Dimerization is a widely believed critical requirement for the yeast transcriptional activator GCN4 specifically recognizing its DNA target sites. Nonetheless, the binding of the monomeric GCN4 to DNA target sites AP-1 and ATF/CREB was recently detected by kinetic studies. Here, for the first time, we present a detailed description of the thermodynamics of a monomeric peptide GCN4-br, the basic region (226-252) of GCN4, binding to AP-1, and ATF/CREB. GCN4 specifically binds to AP-1 and ATF/CREB in the monomeric form as shown by our circular dichroism thermal unfolding measurements. Isothermal titration calorimetry experiments indicate that the binding process of GCN4-br with DNA is enthalpically driven, accompanied by an unfavorable entropy change. The temperature dependence of DeltaH(0) reveals negative changes in heat capacity DeltaC(p): DeltaC(p) = -0.92 kJ. mol(-1) K(-1) and DeltaC(p) = -0.95 kJ. mol(-1) K(-1) for GCN4-br binding to AP-1 and ATF/CREB, respectively, which is a striking manifestation of GCN4-br specifically recognizing DNA target sites. These thermodynamic characteristics may give new insight into the mechanism by which GCN4 protein binds to DNA target sites for its transcriptional regulation.

Activating Transcription Factor 2↗

PubMed2003

Development of a set of expression vectors in Hansenula polymorpha.

Four expression vectors based on formate dehydrogenase promoter (FMDp) and methanol oxidase promoter (MOXp) from Hansenula polymorpha were developed to express heterologous genes in Hansenula polymorpha. A secretion signal sequence of the mating factor-alpha from Saccharomyces cerevisiae was inserted in the secretory expression plasmids for efficient secretion. A modified green fluorescent protein (mGFP5) was used as the marker of expression for the first time in H. polymorpha NCYC495 (leu 1.1) to determine the expression ability of these plasmids. The mGFP5 thus expressed retained its biochemical and physiological properties, such as accumulation inside cells and efficient secretion into the culture media. These results indicated that the four integrative vectors are useful expression systems which could be directly applied for production of heterologous proteins of interests in H. polymorpha.

Alcohol Oxidoreductases↗

PubMed2003

A comparison of folic acid and 5-methyltetrahydrofolate for prevention of DNA damage and cell death in human lymphocytes in vitro.

Folic acid (FA), the most oxidized and stable form of folate, is commonly used as a dietary supplement and in culture media. FA must be reduced and methylated to become the metabolically active form found in blood and utilized by tissues, i.e. 5-methyltetrahydrofolate (5-MeTHF). 5-MeTHF is the methyl group donor required for the conversion of homocysteine to methionine catalyzed by vitamin B(12)-dependent methionine synthase. It is hypothesized that 5-MeTHF may be more effective than FA in reducing spontaneous DNA damage and improving cell proliferation because, unlike FA, it can donate a methyl group for methionine synthesis, which is required for cell division via polyamine production and for maintenance methylation of DNA after its conversion to S-adenosylmethionine. We aimed to determine whether FA and 5-MeTHF differed in their capacity to prevent genetic damage and cell proliferation of human lymphocytes in vitro. Lymphocytes from eight female volunteers (40-48 years) were cultured in RPMI 1640 medium containing 12-120 nM FA or 5-MeTHF for 9 days. Mitogenesis was stimulated with phytohemagglutinin and the medium changed on days 3 and 6. Cytokinesis was inhibited by adding cytochalasin B on day 8 and cells were harvested and transferred to microscope slides on day 9. Chromosome damage, cell death and cytostasis was measured using the cytokinesis-block micronucleus assay in its comprehensive mode. The results showed that the frequency of micronucleated binucleate cells was significantly lower at 120 nM FA compared with 120 nM 5-MeTHF (P < 0.05), however, at 12 nM concentration both forms of folate were associated with increased frequency of micronuclei and nuclear buds relative to 120 nM (P < 0.05). Apoptosis tended to be significantly higher in 5-MeTHF cultures compared with FA cultures, however, necrosis and nuclear division were similar between cultures. We conclude that 5-MeTHF is not more efficient than FA in preventing human lymphocyte genomic instability in this in vitro system. Further research is needed to clarify the role of choline and methionine concentration and the importance of the reduced folate carrier and the folate receptor in determining the relative bioavailability of 5-MeTHF and FA with regard to genome stability.

Adult↗

PubMed2003

Quantification of CCR5 mRNA in human lymphocytes and macrophages by real-time reverse transcriptase PCR assay.

CCR5, a beta-chemokine receptor, plays an important role in human immunodeficiency virus (HIV) infection of human immune cells, as it is a primary coreceptor for HIV entry into macrophages. We have applied a newly developed real-time reverse transcriptase PCR (RT-PCR) assay for the quantification of CCR5 mRNA in human blood immune cells. The CCR5 real-time RT-PCR assay has a sensitivity of 100 mRNA copies, with a dynamic range of detection between 10(2) and 10(6) copies of the CCR5 mRNA transcripts per reaction. The assay is highly reproducible, with an intra-assay coefficient of variation of the threshold cycle of less than 2.07%. When used for quantification of CCR5 mRNA in human monocyte-derived macrophages (MDM) and peripheral blood lymphocytes (PBL), the assay has precision and reproducibility. MDM expressed higher levels of CCR5 mRNA than did PBL. Thus, this assay has the potential and a wide application for the investigation of the role of CCR5 in inflammatory diseases and viral infections, including HIV disease.

Blood Cells↗

PubMed2003

Effects of allicin on both telomerase activity and apoptosis in gastric cancer SGC-7901 cells.

AIM: To investigate the effects of allicin on both telomerase activity and apoptosis in gastric cancer SGC-7901 cells. METHODS: The gastric cancer SGC-7901 adenocarcinoma cells were treated with allicin and the cell cycle, inhibitory rate, apoptosis, telomerase activity and morphologic changes were studied by MTT assay, flow cytometry (FCM), TRAP-PCR-ELISA assay, light microscope, electron microscope respectively. Results were compared with that of AZT (3'-Azido-3'-deoxythymidine). RESULTS: SGC-7901 cells were suppressed after exposure to allicin of 0.016 mg/ml, 0.05 mg/ml, and 0.1 mg/ml for 48 h. Compared with the control, the difference was significant (P<0.05). Allicin could induce apoptosis of the cells in a dose-dependent and non-linear manner and increase the proportion of cells in the G(2)/M phase. Compared with the control, the difference was significant in terms of the percentage of cells in the G2/M phase (P<0.05). Allicin could inhibit telomerase activity in a time-dependent and dose-dependent pattern. After exposure to allicin at 0.016 mg/ml for 24 hours, SGC-7901 cells showed typical morphologic change. CONCLUSION: Allicin can inhibit telomerase activity and induce apoptosis of gastric cancer SGC-7901 cells. Allicin may be more effective than AZT.

Adenocarcinoma↗

PubMed2003

[Perioperative changes in plasma endothelin and calcitonin gene-related peptide in congenital heart disease with pulmonary hypertension].

OBJECTIVE: To assess the perioperative changes in plasma endothelin (ET) and calcitonin gene-related peptide (CGRP) in children with congenital heart disease complicated by pulmonary hypertension. METHODS: In 33 patients, radioimmunoassay was used to measure plasma ET and CGRP levels at different time points: Preoperative, immediate post-op, 3 hrs, 24 hrs, 72 hrs after cardiac surgery with cardiopulmonary bypass. RESULTS: Preoperative plasma ET levels in two groups were markedly increased. The level of ET in group II (severe pulmonary hypertension patients) was significantly higher than those [(138+/-25 compared with 77+/-19)pg/ml, P<0.01] in group I (mild pulmonary hypertension patients). In group I, the plasma ET level rose immediately post-op (P<0.001) and retumed to the initial level after one day (P>0.05). However, in group II plasma ET level was only normalized 3 days post-op (P<0.05). The CGRP level of both group I and group II increased at the first post-op day [(187+/-131 330+/-187)pg/ml], then began to decline by the 3rd day [(88+/-85, 150+/-95) pg/ml]. CONCLUSION: Endothelin and calcitonin gene-related peptide was involved in the pathophysiologic process of pulmonary hypertension and correlated with the degree of pulmonary hypertension. The imbalance of ET and CGRP after cardiopulmonary bypass may affect the prognosis.

Adolescent↗

PubMed2003

[Roles of leptin in the development during girls'puberty].

OBJECTIVES: To study the roles of leptin in the development during puberty in girls and the its relationship with insulin (INS), growth hormone (GH), estradiol (E(2)) and testosterone (T). METHODS: One hundred and fifty girls with simple obese aged 7 to 17 years, and 150 normal healthy girls and 150 girls with malnutrition matched for age (+/- 3 months) and height (+/- 2 cm) were selected. Serum levels of leptin, INS, GH, E(2) and T were measured for them. RESULTS: Their serum level of leptin positively correlated with body mass index (BMI) and age. Serum level of leptin in girls increased steadily from Tanner stage B(1) to stage B(5). At Tanner stage B(2), serum level of leptin in the normal groups (7.72 microg/L) was not significantly different from that in those with malnutrition (7.36 microg/L), but significantly lower than that in the obese groups (12.85 microg/L). At other Tanner stages, there was significant difference in serum level of leptin among obese, normal and malnutrition groups. Serum level of leptin correlated negatively with serum GH and positively with serum INS, but not correlated with E(2) and T. CONCLUSIONS: Leptin may play a role in triggering development during puberty in girls. Serum level of leptin at Tanner stage B(2) may be the threshold dose to trigger the onset of puberty in girls. Quickly increasing level of leptin at Tanner stage B(5) may inhibit the increase of GH, which ushered the end of puberty in girls.

Adolescent↗

PubMed2003

[Study of midazolam for premedication in oral and maxillofacial surgery].

OBJECTIVE: To study the effects of midazolam for premedication in oral-maxillofacial surgery. METHODS: 60 patients were selected and divided into 3 groups equally with 20 cases in each group. Different drugs were used for premedication. Group received midazolam 0.06 mg/kg, group received diazepam 0.12 mg/kg, group received luminal 3 mg/kg, Intramuscular injections of drugs were finished before 30 minutes of anesthesia. The sedative and anxiolytic effects, the changes of circulation and respiration and the side effects were evaluated. RESULTS: In group, BIS (bispectral analysis of electroencephalogram) decreased obviously and Ramsay score increased significantly 5 minutes after drug administration, AVAT(Anxiety visual analog test) and SAI(State anxiety inventory) decreased obviously 30 minutes after administration drug (P < 0.05). But no significant changes in the other groups (P > 0.05). There were no remarkable changes of circulation and respiration in the three groups. No severe side effects were observed after premedication. CONCLUSION: The premedication of using midazolam has good sedative and anxiolytic effects and few side effects.

Adolescent↗

PubMed2003

[Variations of water-soluble carbohydrate and nitrogen contents in Leymus chinensis and Phragmites communis under different stocking rates].

The variations of the contents of water-soluble carbohydrate and nitrogen in L. chinensis and Ph. communis under different stocking rates were studied by fencing grazing experiment on L. chinensis grassland. The results indicated that the water-soluble carbohydrate content in the base stem of L. chinensis and Ph. communis was the lowest (7.12% and 3.95%, respectively) at the beginning of growth period, and then increased gradually with seasons. There was no significant variation in the content of leaf water-soluble carbohydrate in the grasses. L. chinensis germinated earlier than Ph. communis, resulted in the difference between the water-soluble carbohydrate content in the base stem and the leaf of the grasses at the beginning of the experiment in May. Proper stocking rates were favorable for the increase of water-soluble carbohydrate content, and could accelerate the re-growth capability of the herbage. The nitrogen content was the highest at the beginning of growth period, and then decreased gradually with seasons, which was accorded with their phenology. Proper stocking rates could stimulate the assimilation of nitrogen in soil, and bring it to the ground, which improved the nutrition value of the herbage.

Animal Feed↗

PubMed2002

Determination of lomefloxacin by terbium sensitized chemiluminescence method.

A simple, rapid and sensitive chemiluminescence (CL) method was proposed for the determination of lomefloxacin (LFX). This method is based on the fact that the weak CL from the redox reaction of Ce(4+)-Na(2)SO(3) can be greatly enhanced by the complex of Tb(3+)-LFX. The CL intensity is directly proportional to the concentration of LFX in the range 2.0x10(-9) to 1.0x10(-5) mol L(-1), and the detection limit (S/N=3) is 1.1x10(-9) mol L(-1). This method has been applied to the detection of LFX in pharmaceutical preparation, urine and serum samples. Recoveries were in the range 95-105%. The CL mechanism of Ce(4+)-Na(2)SO(3)-Tb(3+)-LFX system was proposed to be an intermolecular energy transfer from excited SO(2)(*) to LFX and an intramolecular energy transfer from LFX to Tb(3+).

Anti-Infective Agents↗

PubMed2002

[Influence of high-frequency electric surgical knife on healing of abdominal incision, experimental and clinical studies].

OBJECTIVE: To study the influence of high-frequency electric surgical knife on abdominal incision healing. METHODS: Two hundred and forty Wistar rats were randomly divided into two groups of 120 rats to undergo abdominal incision by high-frequency electric knife or common lancet respectively. Each of these two groups was redivided into four subgroups that were injected hypodermically with 0.2 ml of quantitative mixture of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa at the concentrations of 0.24 x 10(2) bacteria (10(2) group), 4.49 x 10(4) bacteria (10(5) group), and 4.11 x 10(7) bacteria (10(8) group) respectively, and normal saline of the same volume (10(0) group). Eight days after the operation, the rats were killed. The infection rate of the operational wound was observed and the tissues around the wounds were examined pathologically. On the basis of the animal experiment, 220 patients undergoing abdominal operation above type II were randomly allocated into one of following three groups: high-frequency electric knife (EK) group (93 cases, high-frequency electric knife was used to cut the abdominal tissues and electro-coagulation was used for hemostasis), electro-coagulation (EC) group (55 cases, the abdominal tissues were cut with common lancet and electro-coagulation was used for hemostasis) and control group (72 cases, common lancet and silk thread suture were used). The healing of wound was observed after operation. RESULTS: Four rats died of anesthetic accident; the other 236 rats were killed 8 days after. The wound infection rates were 23.33% and 6.60% in the experimental 10(0) group and the control 10(0) group respectively (chi(2) = 3.28, P > 0.05); 37.04% and 13.33% in the experimental 10(2) group and the control 10(2) group respectively (chi(2) = 4.31, P > 0.05), 50.00% and 24.14% in the experimental 10(5) group and the control 10(5) group respectively (chi(2) = 4.22, P > 0.05); and 63.33% and 36.67% in the experimental 10(8) group and the control 10(8) group respectively (chi(2) = 4.27, P > 0.05). Clinical observation showed a delayed wound healing rate of 17.20% (16 cases) in EK group, 16.36% (11 cases) in EC group, and 2.86% (2 cases) in the control group. There was a statistically significant difference in delayed wound healing rate between the EK and control groups (chi(2) = 8.57, P < 0.01) and between the EC and control groups (chi(2) = 5.66, P < 0.05). However, no significant difference in the delayed wound healing rate was seen between the EK and EC groups (chi(2) = 0.017, P > 0.05). CONCLUSION: High-frequency electric knife remarkably delays the healing of abdominal incision. Its application should be minimized so as to reduce the possibility of postoperative complications.

Abdomen↗

PubMed2002

Genetic variation in the 6p22.3 gene DTNBP1, the human ortholog of the mouse dysbindin gene, is associated with schizophrenia.

Prior evidence has supported the existence of multiple susceptibility genes for schizophrenia. Multipoint linkage analysis of the 270 Irish high-density pedigrees that we have studied, as well as results from several other samples, suggest that at least one such gene is located in region 6p24-21. In the present study, family-based association analysis of 36 simple sequence-length-polymorphism markers and of 17 SNP markers implicated two regions, separated by approximately 7 Mb. The first region, and the focus of this report, is 6p22.3. In this region, single-nucleotide polymorphisms within the 140-kb gene DTNBP1 (dystrobrevin-binding protein 1, or dysbindin) are strongly associated with schizophrenia. Uncorrected, empirical P values produced by the program TRANSMIT were significant (P<.01) for a number of individual SNP markers, and most remained significant when the data were restricted to include only one affected offspring per nuclear family per extended pedigree; multiple three-marker haplotypes were highly significant (P=.008-.0001) under the restricted conditions. The pattern of linkage disequilibrium is consistent with the presence of more than one susceptibility allele, but this important issue is unresolved. The number of markers tested in the adjacent genes, all of which are negative, is not sufficient to rule out the possibility that the dysbindin gene is not the actual susceptibility gene, but this possibility appears to be very unlikely. We conclude that further investigation of dysbindin is warranted.

Animals↗

PubMed2002

Structure of the regulatory N-domain of human cardiac troponin C in complex with human cardiac troponin I147-163 and bepridil.

Cardiac troponin C (cTnC) is the Ca(2+)-dependent switch for contraction in heart muscle and a potential target for drugs in the therapy of heart failure. Ca(2+) binding to the regulatory domain of cTnC (cNTnC) induces little structural change but sets the stage for cTnI binding. A large "closed" to "open" conformational transition occurs in the regulatory domain upon binding cTnI(147-163) or bepridil. This raises the question of whether cTnI(147-163) and bepridil compete for cNTnC.Ca(2+). In this work, we used two-dimensional (1)H,(15)N-heteronuclear single quantum coherence (HSQC) NMR spectroscopy to examine the binding of bepridil to cNTnC.Ca(2+) in the absence and presence of cTnI(147-163) and of cTnI(147-163) to cNTnC.Ca(2+) in the absence and presence of bepridil. The results show that bepridil and cTnI(147-163) bind cNTnC.Ca(2+) simultaneously but with negative cooperativity. The affinity of cTnI(147-163) for cNTnC.Ca(2+) is reduced approximately 3.5-fold by bepridil and vice versa. Using multinuclear and multidimensional NMR spectroscopy, we have determined the structure of the cNTnC.Ca(2+).cTnI(147-163).bepridil ternary complex. The structure reveals a binding site for cTnI(147-163) primarily located on the A/B interhelical interface and a binding site for bepridil in the hydrophobic pocket of cNTnC.Ca(2+). In the structure, the N terminus of the peptide clashes with part of the bepridil molecule, which explains the negative cooperativity between cTnI(147-163) and bepridil for cNTnC.Ca(2+). This structure provides insights into the features that are important for the design of cTnC-specific cardiotonic drugs, which may be used to modulate the Ca(2+) sensitivity of the myofilaments in heart muscle contraction.

Actin Cytoskeleton↗

PubMed2002

Kinetic studies of calcium and cardiac troponin I peptide binding to human cardiac troponin C using NMR spectroscopy.

Ca2+ and human cardiac troponin I (cTnI) peptide binding to human cardiac troponin C (cTnC) have been investigated with the use of 2D [1H,15N] HSQC NMR spectroscopy. The spectral intensity, chemical shift, and line-shape changes were analyzed to obtain the dissociation ( K(D)) and off-rate ( k(off)) constants at 30 degrees C. The results show that sites III and IV exhibit 100-fold higher Ca2+ affinity than site II ( K(D(III,IV)) approximately 0.2 microM, K(D(II)) approximately 20 microM), but site II is partially occupied before sites III and IV are saturated. The addition of the first two equivalents of Ca2+ saturates 90% of sites III and IV and 20% of site II. This suggests that the Ca2+ occupancy of all three sites may contribute to the Ca2+-dependent regulation in muscle contraction. We have determined a k(off) of 5000 s(-1) for site II Ca2+ dissociation at 30 degrees C. Such a rapid off-rate had not been previously measured. Three cTnI peptides, cTnI(34-71), cTnI(128-147), and cTnI(147-163), were titrated to Ca2+-saturated cTnC. In each case, the binding occurs with a 1:1 stoichiometry. The determined K(D) and k(off) values are 1 microM and 5 s(-1) for cTnI(34-71), 78+/-10 microM and 5000 s(-1) for cTnI(128-147), and 150+/-10 microM and 5000 s(-1) for cTnI(147-163), respectively. Thus, the dissociation of Ca2+ from site II and cTnI(128-147) and cTnI(147-163) from cTnC are rapid enough to be involved in the contraction/relaxation cycle of cardiac muscle, while that of cTnI(34-71) from cTnC may be too slow for this process.

Calcium↗

PubMed2002

C-fos and c-jun expressions in nitric oxide synthase immunoreactive neurons in the lateral geniculate nucleus of experimental glaucomatous rats.

The present study was initiated to investigate the expressions of c-fos and c-jun in nitric oxide synthase immunoreactive neurons and their possible roles in the lateral geniculate nucleus (LGN) of glaucomatous rats. An experimental one-eye glaucoma model was created by cauterisation of the limbal-derived veins. Animals were killed by cardiac perfusion, and brains containing the LGN were removed and processed for c-fos, c-jun and neuronal nitric oxide synthase (nNOS) immunohistochemistry. No c-fos or c-jun immunoreactivity was observed in the LGN of control rats. In the glaucomatous rats, expression of c-fos and c-jun was induced bilaterally in the ventral LGN (vLGN) as early as 2 h postoperation. The number of c-fos-immunopositive cells increased at 1 and 2 days postoperation in both the lateral and medial subdivisions of the vLGN (vLGN-l and vLGN-m). Thereafter, the expression decreased and was totally absent at 1 and 2 weeks. No c-fos was induced in the dorsal LGN (dLGN). C-jun-immunopositive cells were mainly localised in the intergeniculate leaflet and vLGN. Few neurons were observed in the dLGN. The number of c-jun-immunopositive cells decreased at 1 and 2 weeks postoperation. Some of the c-fos- and c-jun-immunopositive cells were also nNOS immunopositive. The present results reveal that glaucoma activates the expressions of immediate early genes (IEGs) in some cells of the LGN. It is postulated that they may play important roles in the pathologic processes of glaucoma. The relationship between these IEGs and nitric oxide was also discussed.

Animals↗