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991.
GABA(B) receptor-mediated regulation of P2X7 receptor expression in the gerbil hippocampus 总被引:2,自引:0,他引:2
In the present study, the P(2)X(7) receptor expression in the gerbil hippocampus and GABA-mediated responses of its expression was investigated in order to identify the roles of the P(2)X(7) receptor on seizure activity and recovery mechanisms. P(2)X(7) receptor immunoreactivity in seizure-resistant (SR) gerbils was similar to that in pre-seizure group of seizure-sensitive (SS) gerbils. The administration of baclofen, a GABA(B) receptor agonist, P(2)X(7) receptor immunoreactivity was decreased in the mossy fiber, compared with that of non-treated gerbils, whereas treatment with phaclofen, a GABA(B) receptor antagonist, elevated P(2)X(7) receptor expression. Neither the treatments with GABA(A) receptor agonist nor antagonist affected P(2)X(7) receptor expression in the hippocampus. These findings suggest that altered P(2)X(7) receptor expression may not be involved in the epileptogenesis or seizure activity in gerbils, and presynaptic GABA(B) receptor-mediated actions may be closely related with the regulation of P(2)X(7) receptor expression in the gerbil hippocampus. 相似文献
992.
993.
Injection of orexin A into the diagonal band of Broca induces sympathetic and hyperthermic reactions
This experiment tested the effect of an injection of orexin A into the diagonal band of Broca on the sympathetic activity and body temperature. Concentration of glycerol into white fat of lumbar region, firing rates of sympathetic nerves to interscapular brown adipose tissue (IBAT), IBAT and colonic temperatures, and heart rate were monitored in urethane-anesthetized male Sprague-Dawley rats for 30 min before and 150 min after injections of orexin A (0.4 and 0.7 nmol) into the diagonal band of Broca. The same variables were monitored in control rats with an injection of saline. The results show that orexin A increases glycerol concentration, sympathetic firing rate, IBAT and colonic temperatures, and heart rate. The saline injection did not induce any modification. These findings suggest that the diagonal band of Broca is a cerebral structure involved in the induction of the hyperthermia due to orexin A. 相似文献
994.
Shin HY Shin TY Seo SW An HJ Kwon YT Song BK Lee EJ Kim SH Kim YK Hong SH Kim HM 《Biological & pharmaceutical bulletin》2004,27(10):1521-1526
WooKiEum (WKE) has been used for the purpose of the development of increased immune-system strength in Korea. In the present study, we examined the anti-immobility effect of WKE on the forced swimming test (FST), and then measured blood biochemical parameters related to fatigue: glucose (Glc), blood urea nitrogen (BUN), lactic dehydrogenase (LDH), creatinine, and total protein (TP). WKE (0.1, 1 g/kg) was administered orally to mice for 7 d. After 2 d, the immobility time was decreased in the WKE-administered group. After 7 d, the immobility time was significantly decreased in the WKE-administered group (64.6+/-9.0 s for 0.1 g/kg) in comparison with the control group (101.3+/-32.7 s). In addition, amount of Glc in the blood serum was increased, whereas the contents of BUN, LDH and TP decreased in the WKE-administered group. Next, we investigated the effect of WKE on the production of cytokines in a human T-cell line, MOLT-4 cells and mouse peritoneal macrophages. WKE (1 mg/ml) significantly increased interferon (IFN)-gamma and TNF-alpha production compared with the media control (about 2.2-fold for IFN-gamma, about 1.7-fold for TNF-alpha, p<0.05) after 24 h. WKE increased the protein expression of IFN-gamma in MOLT-4 cells. These results suggest that WKE may be useful in immune function improvement. 相似文献
995.
Apoptosis induction by 4beta-acetoxyscirpendiol from Paecilomyces tenuipes in human leukaemia cell lines 总被引:1,自引:0,他引:1
The carpophores of Paecilomyces tenuipes are known in the Orient for their strong antitumor activity. In continuation of our study on acetoxyscirpendiol (ASD, 4beta-acetoxyscirpene-3alpha,15-diol) as a cytotoxic component from this fungus, we report particularly on the mode of action of ASD in inducing apoptosis in human MOLT-4, THP-1 and Jurkat T cell leukaemia in vitro. The antiproliferative effects of ASD seem attributable to its induction of apoptosis in the cells, as it blocked the cell cycle, induced hypodiploidity and bound annexin V and also cleaved poly-(ADP-ribose) polymerase (PARP) in these cell lines. The 50% inhibitory concentrations (IC50) of ASD on MOLT-4, THP-1 and Jurkat T cells were found to be 60, 85 and 60 ng/ml, respectively. ASD arrested the cell cycle at the G1/S transition and showed hypodiploidity due to the accumulation of sub-G0 population. Annexin V binding was increased in the presence of ASD in the MOLT-4 cell line in a time-dependent manner. ASD and three of its derivatives also induced cleavage of PARP in both MOLT-4 and Jurkat T cell lines. From these data, it is suggested that ASD exerts its cytotoxic activity by inducing apoptosis in leukaemia cell lines in vitro. 相似文献
996.
Proteomics analysis of differentially expressed metastasis-associated proteins in adenoid cystic carcinoma cell lines of human salivary gland 总被引:4,自引:0,他引:4
Metastasis is the most insidious and life threatening aspect of cancers. However little is known about the molecular mechanisms of tumor metastasis. A poorly metastatic Acc-2 cell line and highly metastatic Acc-M cell line were selected as an experimental model to study on metastatic mechanisms and antimetastatic procedures. In the present study, two-dimensional gel electrophoresis and mass spectrometry are combined to approach the protein profiles associated with tumor metastasis between Acc-2 and Acc-M cell lines. Image analysis of silver stained 2-dimensional gels revealed that 12 protein spots showed significantly quantitative and qualitative variations and mass spectrometry is utilized to further identify these spots. Of the identified proteins, transketolase, Dim1p, v-Ha-ras oncogene, type I collagen pro alpha, tumor necrosis factor (ligand) superfamily member 4, and pirin etc, have shown associations with distinct aspect of tumor metastasis to some extent. The dissimilar expression patterns of these 12 spots indicate the different roles they may play involved in tumor metastasis. 相似文献
997.
Koeberl DD Young SP Gregersen NS Vockley J Smith WE Benjamin DK An Y Weavil SD Chaing SH Bali D McDonald MT Kishnani PS Chen YT Millington DS 《Pediatric research》2003,54(2):219-223
Tandem mass spectrometry was adopted for newborn screening by North Carolina in April 1999. Since then, three infants with short-chain acyl-CoA dehydrogenase (SCAD) and one with isobutyryl-CoA dehydrogenase deficiency were detected on the basis of elevated butyrylcarnitine/isobutyrylcarnitine (C4-carnitine) concentrations in newborn blood spots analyzed by tandem mass spectrometry. For three SCAD-deficient infants, biochemical evaluation included a plasma acylcarnitine profile with markedly elevated C4-carnitine, urine organic acid analysis with markedly elevated ethylmalonic and 2-methylsuccinic acids, and markedly elevated [U-13C]butyrylcarnitine concentrations in medium from fibroblasts incubated with [U-13C]palmitic acid and excess l-carnitine, consistent with classic SCAD deficiency. Two of three infants diagnosed with classic SCAD deficiency remained asymptomatic; however, the third infant presented with seizures and a cerebral infarct at 10 wk of age. All three infants had putatively inactivating mutations in both alleles of the SCAD gene. The highly elevated plasma C4-carnitine levels in the three infants detected by newborn screening tandem mass spectrometry differentiated them from infants and children who were homozygous or compound heterozygous for one of two SCAD gene susceptibility variations; for the latter group the C4-carnitine levels were normal. Isobutyryl-CoA dehydrogenase deficiency in a fourth infant was confirmed after isolated elevation of C4-carnitine in the acylcarnitine profile. 相似文献
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