OBJECTIVETo explore electrophysiology mechanism of acupuncture for treatment and prevention of visual deprivation effect.

METHODSEighteen healthy 15-day Evans rats were randomly divided into a normal group, a model group and an acupuncture group, 6 rats in each one. Deprivation amblyopia model was established by monocular eyelid suture in the model group and acupuncture group. Acupuncture was applied at "Jingming" (BL 1), "Chengqi" (ST 1), "Qiuhou" (EX-HN 7) and "Cuanzhu" (BL 2) in the acupuncture group. The bilateral acupoints were selected alternately, one side for a day, and totally 14 days were required. The effect of acupuncture on visual evoked potential in different spatial frequencies was observed.

METHODSUnder three different kinds of spatial frequencies of 2 X 2, 4 X 4 and 8 X 8, compared with normal group, there was obvious visual deprivation effect in the model group where P1 peak latency was delayed (P<0.01) while N1 -P1 amplitude value was decreased (P<0.01). Compared with model group, P1 peak latency was obviously ahead of time (P<0.01) while N1-P1 amplitude value was increased (P<0.01) in the acupuncture group, there was no statistical significance compared with normal group (P>0.05). Under spatial frequency of 4 X 4, N1-P1 amplitude value was maximum in the normal group and acupuncture group. With this spatial frequency the rat's eye had best resolving ability, indicating it could be the best spatial frequency for rat visual system.

CONCLUSIONThe visual system has obvious electrophysiology plasticity in sensitive period. Acupuncture treatment could adjust visual deprivation-induced suppression and slow of visual response in order to antagonism deprivation effect.

Acupuncture Points ; Acupuncture Therapy ; Amblyopia ; physiopathology ; therapy ; Animals ; Evoked Potentials, Visual ; Female ; Humans ; Male ; Rats ; Rats, Long-Evans

BACKGROUND: Various studies and experimental trials have been done to develop bioprosthetic devices to treat complex congenital heart disease due to the limited usage of homograft tissue. The purpose of the present study was to evaluate the effect of diamine bridges with using L-lysine, as compared with using ethanol. MATERIAL AND METHOD: Porcine pericardium was fixed at 0.625% GA (commercial fixation). An interim step of ethanol (80%; 1 day at room temperature) or L-lysine (0.1 M; 2 days at 37degrees C) was followed by completion of the GA fixation (2 days at 4degrees C and 7 days at room temperature). The tensile strength and thickness of the porcine percardium were measured, respectively. The treated pericardiums were implanted subcutaneously into three-week old Long-Evans rats for 8 weeks. The calcium content of the implants was assessed by atomic absorption spectroscopy and the histology. RESULT: Ethanol pretreatment (13.6+/-10.0 ug/mg, p=0.008), L-lysine pretreatment (15.3+/-1.0 ug/mg, p=0.002), and both treatment (16.1+/-11.1 ug/mg, p=0.012) significantly inhibited calcification, as compared with the controls (51.2+/-8.5 ug/mg). L-lysine pretreatment (0.18+/-0.02 mm, 1.20+/-0.30 kg f/5 mm) significantly increased the thickness and tensile strength, as compared with ethanol pretreatment (0.13+/-0.03 mm, 0.85+/-0.36 1.0 kg f/5 mm) (p<0.01, p=0.035). CONCLUSION: The diamine bridges using L-lysine seemed to decrease the calcification of porcine pericardium fixed with glutaraldehyde, and this was comparable with Ethanol. Additionally, it seemed to enhance the thickness and tensile strength.
Absorption ; Bioprosthesis ; Calcium ; Ethanol ; Glutaral ; Heart Diseases ; Lysine ; Pericardium ; Rats, Long-Evans ; Spectrum Analysis ; Tensile Strength ; Transplantation, Heterologous ; Transplantation, Homologous

OBJECTIVETo investigate the association between plasma adiponectin and insulin resistance in OLETF rats.

METHODSTwenty male Otsuka Long-Evans Tokushima Fatty (OLETF) rats and 10 male Long-evans Tokushima Otsuka (LETO) rats underwent oral glucose tolerance test (OGTT) at 13 and 40 weeks of age. At 8, 32 and 40 weeks of age, the rats were sacrificed to measure the blood glucose, plasma insulin and adiponectin levels, and serum levels of TG, CHOL and FFA.

RESULTSThe plasma adiponectin level was significantly decreased in 8-week-old OLETF rats compared with that of LETO rats (P<0.05). The plasma insulin level, TG, CHOL, and FFA were significantly higher in OLETF rats than in LETO rats at 32 and 40 weeks of age.

CONCLUSIONA decreased plasma level of adiponectin preludes insulin resistance and is inversely correlated to insulin sensitivity. Hypoadiponectinemia may be an important reason leading to insulin resistance.

Adiponectin ; blood ; Animals ; Diabetes Mellitus, Type 2 ; blood ; metabolism ; Insulin ; pharmacology ; Insulin Resistance ; Male ; Rats ; Rats, Inbred OLETF ; Rats, Long-Evans

Glutamine synthetase (GS) is a key enzyme in the regulation of glutamate neurotransmission in the central nervous system. It is responsible for converting glutamate to glutamine, consuming one ATP and NH3 in the process. Glutamate is neurotoxic when it accumulates in extracellular fluids. We investigated the effects of GS in both a spinal cord injury (SCI) model and normal rats. 0.1-ml of low (2-microM) and high (55-microM) concentrations of GS were applied, intrathecally, to the spinal cord of rats under pentobarbital anesthesia. Immediately after an intrathecal injection into the L1-L3 space, the rats developed convulsive movements. These movements initially consisted of myoclonic twitches of the paravertebral muscles close to the injection site, repeated tonic and clonic contractions and extensions of the hind limbs (hind limb seizures) that spread to the fore limbs, and finally rotational axial movements of the body. An EMG of the paravertebral muscles, fore and hind limbs, showed the extent of the muscle activities. GS (2-microM) caused spinal seizures in the rats after the SCI, and GS (6-microM) produced seizures in the uninjured anesthetized rats. Denatured GS (70 degrees C, 1 hour) also produced spinal seizures, although higher concentrations were required. We suggest that GS may be directly blocking the release of GABA, or the receptors, in the spinal cord.
Animals ; Electromyography ; Female ; *Glutamate-Ammonia Ligase/administration & dosage ; Injections, Spinal ; Male ; Rats ; Rats, Long-Evans ; Seizures/*chemically induced/physiopathology ; Spinal Cord Diseases/*chemically induced/physiopathology

OBJECTIVE: The purpose of this study is to determine neurotrophin effect in Fe++-induced experimental spinal cord injury in adult female rat. METHOD: Thirty Long-Evans rats (weight, 250 to 300 gr) were divided into 6 groups. Group I was control group. Group II was Fe-only group. Group III was NGF-only group. Group IV was NGF-Fe group. Group V was NT4-only group. Group VI was NT4-Fe group. For all experimental animals spinal cord was exposed by T10 laminectomy. Neurtrophin and Fe++ was injected at spinal cord directly by glass needle with ~100 um diameter mounted on Hamilton syringe. Animals were sacrificed, spinal cord was extracted and prepared in sagittal section. Tissues were stained with LFB, NeuN and APC staining method. The amount of spinal cord damage was measured at 3 different locations under the microscope. RESULTS: Fe-only group showed more damage than the control group. NGF-only group showed the same result as the control group. NT4-only group showed more damage than the control group in LFB staining. NGF-Fe group showed the same result as Fe-only group. NT4-Fe group showed more damage than Fe-only group. CONCLUSION: NGF has no additional effect, but NT4 potentiated Fe toxicity in Fe-induced experimental spinal cord injury. NT4 seems to be toxic to rat spinal cord in high dose.
Adult ; Animals ; Female ; Glass ; Humans ; Laminectomy ; Models, Animal ; Needles ; Nerve Growth Factor ; Rats* ; Rats, Long-Evans ; Spinal Cord Injuries* ; Spinal Cord* ; Syringes

OBJECTIVETo study the effects of Liuweidihuang (LWDH) pills on plasma adiponectin level in Otsuka Long-Evans Tokushima Fatty (OLETF) rats.

METHODSForty male OLETF rats were randomized into LWDH and control OLETF groups (n=20), and 10 male Long-Evans Tokushima Otsuka (LETO) rats served as the normal control group (LETO group). The rats in LWDH group were given LWDH pills (daily dose of 2.4 mg/kg) intragastrically since the age of 8 weeks, and the two control groups received water only. Regular blood glucose test was performed using oral glucose tolerance test, and the body weight and food intake of the rats were recorded on a weekly basis. At 8, 32 and 40 weeks of age, respectively, the rats were sacrificed for measurement of plasma adiponectin and plasma insulin.

RESULTSThe food intake of the OLETF rats in both groups were significantly greater than the LETO rats (P<0.01). The rats in LWDH group developed diabetes since 30 weeks of age with an incidence of 28.6% at 40 weeks, which was significantly lower than that in the control OLETF rats (P< 0.01).

CONCLUSIONPlasma adiponectin level is positively correlated to insulin sensitivity in OLETF rats, in which LWDH pills can increase the plasma level of adiponectin and improve the status of insulin resistance.

Adiponectin ; blood ; Animals ; Diabetes Mellitus, Type 2 ; blood ; physiopathology ; prevention & control ; Drugs, Chinese Herbal ; pharmacology ; Eating ; drug effects ; Hypoglycemic Agents ; pharmacology ; Insulin ; blood ; Insulin Resistance ; Male ; Random Allocation ; Rats ; Rats, Inbred OLETF ; Rats, Long-Evans

PURPOSE: Diabetic nephropathy is the most serious of complications in diabetes mellitus. Thiazolidinedione (TZD) is thought to ameliorate diabetic nephropathy; however, the mechanism underlying this effect has not been elucidated. We hypothesized that the vascular endothelial growth factor (VEGF) participates in the pathogenesis of diabetic nephropathy and that TZD may be beneficial for the treatment of diabetic nephropathy because of the effect it has on VEGF. MATERIALS AND METHODS: 23 Otsuka- Long-Evans-Tokushima-Fatty (OLETF) rats and eight control Long-Evans-Tokushima-Otsuka (LETO) rats were divided into the following four groups: LETO group, control OLETF group, pioglitazone treated group (10mg/kg/day), and rosiglitazone treated group (3mg/kg/day). RESULTS: A progressive increase in urinary protein excretion was observed in the diabetic rats. Glomerular VEGF expression in the control OLETF rats was significantly higher than in the control LETO rats. However, there was a significant reduction in both the glomerular VEGF expression and the VEGF mRNA levels after treatment with pioglitazone and rosiglitazone. The twenty-four hour urine protein levels were significantly decreased in both groups of the treated OLETF rats. CONCLUSION: These results suggest that TZD may have beneficial effects on diabetic nephropathy by reducing the VEGF expression.
Vascular Endothelial Growth Factor A/genetics ; Thiazolidinediones/*therapeutic use ; Rats, Long-Evans ; Rats ; Male ; Hypoglycemic Agents/therapeutic use ; Disease Models, Animal ; Diabetic Nephropathies/*drug therapy ; Diabetes Mellitus, Type 2/*drug therapy ; Animals

Recent clinical trials have reported that methylprednisolone sodium succinate administered within 8 hours improves neurological recovery in human spinal cord injury (SCI). Methylprednisolone, however, was ineffective and possibly even deleterious when given more than 8 hours after injury. This finding suggests that a therapeutic time window exists in spinal cord injury. In order to determine the doses, durations and timing of methylprednisolone treatment for optimal neuroprotection, a single or two bolus dose of methylprednisolone (30 mg/kg) was administered at 10, 30, 120, 150 and 240 min. after three graded spinal cord injury. The primary outcome measure was 24-hour spinal cord lesion volumes estimated from spinal cord Na+ and K+ shifts. A single 30 mg/kg dose of methylprednisolone at 10 min. after injury significantly reduced 24-hour lesion volumes in injured rat spinal cords. However, any other methylprednisolone treatment starting 30 min. or more after injury had no effect on 24-hour lesion volumes compared to the vehicle control group. Moreover, delayed treatment increased lesion volumes in some cases. These results suggest that the NYU SCI model has a very short therapeutic window.
Animal ; Drug Administration Schedule ; Male ; Methylprednisolone Hemisuccinate/therapeutic use ; Methylprednisolone Hemisuccinate/administration & dosage* ; Neuroprotective Agents/therapeutic use ; Neuroprotective Agents/administration & dosage* ; Rats ; Rats, Long-Evans ; Spinal Cord/pathology ; Spinal Cord Injuries/pathology ; Spinal Cord Injuries/drug therapy*

PURPOSE: Obesity is a risk factor for asthma and type II diabetes. Peroxisome proliferator-activated receptor (PPAR)-gamma has been suggested to regulate inflammatory responses in diabetes and asthma. We investigated whether PPAR-alpha, PPAR-gamma, adiponectin receptors (AdipoR1, AdipoR2), leptin, and tumor necrosis factor (TNF)-alpha are expressed in rat lung tissues and whether the expression differs between obese Otsuka Long-Evans Tokushima Fatty (OLETF) and lean Long Evans Tokushima Otsuka (LETO) rats. MATERIALS AND METHODS: Obese and lean rats were given with a high fat diet or a 30% restricted diet for 32 weeks, and their blood glucose levels and weights were monitored. After 32 weeks, mRNA levels of PPAR-alpha, PPAR-gamma, AdipoR1, AdipoR2, leptin, and TNF-alpha in lung tissues were measured using real time PCR. RESULTS: PPAR-alpha, PPAR-gamma, AdipoR1, AdipoR2, leptin, and TNF-alpha were expressed in both obese and lean rat lung tissues. Increased serum glucose levels on intraperitoneal glucose tolerance testing and a higher weight gain at 32 weeks were observed in OLETF control rats compared to OLETF diet restricted rats. PPAR-gamma expression was markedly elevated in obese control and diet restricted rats compared to lean rats, although PPAR-gamma expression in obese rats was not affected by diet restriction. Leptin was highly expressed in OLETF rats compared to LETO rats. TNF-alpha expression was enhanced in OLETF control rats compared LETO diet restricted rats, and decreased by diet restriction. PPAR-alpha, AdipoR1, and AdipoR2 expression were not significantly different between obese and lean rats. CONCLUSION: PPAR-gamma was highly expressed in the lung tissues of obese rats and may be a novel treatment target for regulating lung inflammation associated with obesity.
Animals ; Body Weight ; Glucose Tolerance Test ; Leptin/genetics/metabolism ; Lung/*metabolism ; Male ; Obesity/genetics/*metabolism ; PPAR gamma/genetics/*metabolism ; RNA, Messenger/metabolism ; Rats ; Rats, Long-Evans ; Receptors, Adiponectin/genetics/metabolism ; Tumor Necrosis Factor-alpha/genetics/metabolism

BACKGROUNDMany studies have suggested that the imbalance of angiogenic factor and anti-angiogenic factor expression contributes significantly to the development of choroidal neovascularization (CNV), and ultrasound microbubble combination system can increase the gene transfection efficiency successfully. This study was designed to investigate whether ultrasound-mediated microbubble destruction could effectively deliver therapeutic plasmid into the retina of rat, and whether gene transfer of pigment epithelium-derived factor (PEDF) could inhibit CNV.

METHODSHuman retinal pigment epithelial cells were isolated and treated either with ultrasound or plasmid alone, or with a combination of plasmid, ultrasound and microbubbles to approach feasibility of microbubble-enhanced ultrasound enhance PEDF gene expression; For in vivo animal studies, CNV was induced by argon lasgon laser in rats. These rats were randomly assigned to five groups and were treated by infusing microbubbles attached with the naked plasmid DNA of PEDF into the vitreous of rats followed by immediate ultrasound exposure (intravitreal injection); infusing liposomes with the naked plasmid DNA of PEDF into the vitreous (lipofectamine + PEDF); infusing microbubbles attached with PEDF into the orbit of rats with ultrasound irradiation immediately (retrobular injection); infusing microbubbles attached with PEDF into the femoral vein of rats with exposed to ultrasound immediately (vein injection). The CNV rats without any treatment served as control. Rats were sacrificed and eyes were enucleated at 7, 14, and 28 days after treatment. Gene and protein expression of PEDF was detected by quantitative real-time RT-PCR, Western blotting and immunofluorescence staining, respectively. The effect of PEDF gene transfer on CNV was examined by fluorescein fundus angiography.

RESULTSIn vitro cell experiments showed that microbubbles with ultrasound irradiation could significantly enhance PEDF delivery as compared with microbubbles or ultrasound alone. In the rat CNV model, transfection efficiency mediated by ultrasound/microbubbles was significantly higher than that by lipofectamine-mediated gene transfer at 28 days after treatment. The study also showed that with the administration of ultrasound-mediated microbubbles destruction, the CNV of rats was inhibited effectively.

CONCLUSIONSUltrasound-microbubble technique could increase PEDF gene transfer into rats' retina and chorioid, in association with a significant inhibition of the development of CNV, suggesting that this noninvasive gene transfer method may provide a useful tool for clinical gene therapy.

Animals ; Cells, Cultured ; Choroidal Neovascularization ; prevention & control ; Eye Proteins ; genetics ; Female ; Genetic Therapy ; Humans ; Microbubbles ; Nerve Growth Factors ; genetics ; RNA, Messenger ; analysis ; Rats ; Rats, Long-Evans ; Retina ; metabolism ; Serpins ; genetics ; Transfection ; Ultrasonics