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1.
The objective of this study was to quantify the duration of the hemodynamic activity of N(G)-nitro-l-arginine methyl ester (l-NAME) in a variety of different tissues following a single bolus injection of this nitric oxide synthase inhibitor to healthy rats. l-NAME (15 micromol x kg(-1)) was injected (ip) into rats to produce maximal inhibition of endothelial cell NOS. Animals were subsequently anesthetized and blood flow was quantified using the radioactive microsphere/reference organ technique. At 1 h following a single bolus injection of l-NAME blood flow was reduced to the entire gastrointestinal tract, pancreas, and liver. Three hours following l-NAME administration, blood flow to the stomach and upper small intestine had returned to pretreatment levels; however, blood flow to the jejunum, ileal-jejunal junction, and colon remained significantly reduced. Splenic blood flow was significantly reduced and hepatic arterial blood flow was further reduced at this time as well. After 6 h following l-NAME administration, blood flow in all organs had completely recovered to control levels. Although cardiac index and total peripheral resistance had also returned to preinjection values at this time, mean arterial pressure remained elevated at 6 h posttreatment. Blood flow to the brain, lungs, and psoas muscle were unaffected by l-NAME administration at any time point. Taken together, these data demonstrate a differential regulation of vascular tone by NO in different vascular beds and, depending upon the organ system in question, the vasoactive activity of l-NAME may last from 3 to 6 h following a single bolus injection of this NOS inhibitor. 相似文献
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Charles Romeo Naoko Moriwaki Kerry T. Yasunobu Irwin C. Gunsalus Hideo Koga 《Journal of Protein Chemistry》1987,6(3):253-261
The first 12 NH2-terminal amino acids of the Pseudomonas putida putidaredoxin reductase were shown to be Met-Asn-Ala-Asn-Asp-Asn-Val-Val-Ile-Val-Gly-Thr. Comparison of these data with the DNA sequence of the BamHI-HindIII 197-base fragment derived from the PstI 2.2-kb fragment obtained from the P. putida plasmid showed that the putidaredoxin reductase gene was downstream from the cytochrome P-450 gene and the intergenic region had the 24-nucleotide sequence TAAACACATGGGAGTGCGTGCTAA. The Shine-Dalgarno sequence GGAG was detected in this region. The initiating triplet for the reductase gene was GTG, which normally codes for valine, but in the initiating codon position codes for methionine. From the amino acid sequence and X-ray data comparisons with other flavoproteins, what appears to be the AMP binding region of the FAD can be recognized in the NH2-terminal portion of the reductase involving residues 5–35.This article was presented during the proceedings of the International Conference on Macromolecular Structure and Function, held at the National Defence Medical College, Tokorozawa, Japan, December 1985. 相似文献
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In recent years, rare earth elements (REEs) have been widely used in various modern technological devices and the global demand for REE has been increasing. The increased demand for REEs has led to environmental exposure or water pollution from rare earth metal mines and various commercial products. Therefore, the development of a safe technology for the separation and adsorption of REEs is very important from the perspective of green chemistry and environmental pollution. In this review, the application and mechanisms of microorganisms for the removal and extraction of REEs from aqueous solutions are described. In addition, the advantages in using microorganisms for REE adsorption and future studies on this topic are discussed. 相似文献
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Aiko Shinko Takashi Agari Masahiro Kameda Takao Yasuhara Akihiko Kondo Judith Thomas Tayra Kenichiro Sato Tatsuya Sasaki Susumu Sasada Hayato Takeuchi Takaaki Wakamori Cesario V. Borlongan Isao Date 《PloS one》2014,9(7)
In clinical practice, deep brain stimulation (DBS) is effective for treatment of motor symptoms in Parkinson’s disease (PD). However, the mechanisms have not been understood completely. There are some reports that electrical stimulation exerts neuroprotective effects on the central nervous system diseases including cerebral ischemia, head trauma, epilepsy and PD, although there are a few reports on neuroprotective effects of spinal cord stimulation (SCS). We investigated the neuroprotective effects of high cervical SCS on PD model of rats. Adult female Sprague-Dawley rats received hour-long SCS (2, 50 or 200 Hz) with an epidural electrode at C1–2 level for 16 consecutive days. At 2 days after initial SCS, 6-hydroxydopamine (6-OHDA) was injected into the right striatum of rats. Behavioral evaluations of PD symptoms were employed, including cylinder test and amphetamine-induced rotation test performed at 1 and 2 weeks after 6-OHDA injection. Animals were subsequently euthanized for immunohistochemical investigations. In order to explore neurotrophic and growth factor upregulation induced by SCS, another cohort of rats that received 50 Hz SCS was euthanized at 1 and 2 weeks after lesion for protein assays. Behavioral tests revealed that the number of amphetamine-induced rotations decreased in SCS groups. Immunohistochemically, tyrosine hydroxylase (TH)-positive fibers in the striatum were significantly preserved in SCS groups. TH-positive neurons in the substantia nigra pars compacta were significantly preserved in 50 Hz SCS group. The level of vascular endothelial growth factor (VEGF) was upregulated by SCS at 1 week after the lesion. These results suggest that high cervical SCS exerts neuroprotection in PD model of rats, at least partially by upregulation of VEGF. SCS is supposed to suppress or delay PD progression and might become a less invasive option for PD patients, although further preclinical and clinical investigations are needed to confirm the effectiveness and safety. 相似文献
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Plant Ecology - Japanese stinging nettles, Urtica thunbergiana, in Nara Park (660 ha), central Japan, where several hundred sika deer Cervus nippon have been protected for... 相似文献
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Yusuke Kawazoe Mutsumi Miyauchi Atsuhiro Nagasaki Hisako Furusho Syunryo Yanagisawa Chea Chanbora Toshihiro Inubushi Hideyuki Hyogo Takashi Nakamoto Keiko Suzuki Sawako Moriwaki Susumu Tazuma Shumpei Niida Takashi Takata 《PloS one》2015,10(9)
Background
Cholestatic liver diseases exhibit higher levels of serum γ-glutamyl transpeptidase (GGT) and incidence of secondary osteoporosis. GGT has been identified as a novel bone-resorbing factor that stimulates osteoclast formation. The aim of this study was to elucidate the interaction of elevated GGT levels and cholestatic liver disease-induced bone loss.Methods
Wistar rats were divided into three groups: sham-operated control (SO) rats, bile duct ligation (BDL) rats, and anti-GGT antibody-treated BDL rats (AGT). Serum GGT level was measured. Bone mineral density (BMD) was analyzed by dual-energy X-ray absorptiometry. Bone morphometric parameters and microarchitectural properties were determined by micro-computed tomography and histomorphometry of the distal metaphysis of femurs. Alterations of bone metabolism-related factors were evaluated by cytokine array. Effects of GGT on osteoblasts or stromal cells were evaluated by RT-PCR, enzyme activity, and mineralization ability.Results
Serum levels of GGT were significantly elevated in the BDL-group. In the BDL group, BMD, bone mass percentage, and osteoblast number were significantly decreased, whereas osteoclast number was significantly increased. These alterations were markedly attenuated in the AGT group. The mRNA levels of vascular endothelial growth factor-A, LPS-induced CXC chemokine, monocyte chemoattractant protein-1, tumor necrosis factor-α interleukin-1β and receptor activator of nuclear factor-kappa B ligand were upregulated, and those of interferon-γ and osteoprotegerin were downregulated in the GGT-treated stromal cells. Furthermore, GGT inhibited mineral nodule formation and expression of alkaline phosphatase and bone sialo-protein in osteoblastic cells.Conclusion
Our results indicate that elevated GGT level is involved in hepatic osteodystrophy through secretion of bone resorbing factor from GGT-stimulated osteoblasts/bone marrow stromal cells. In addition, GGT also possesses suppressive effects on bone formation. Managing elevated GGT levels by anti-GGT antibody may become a novel therapeutic agent for hepatic osteodystrophy in chronic liver diseases. 相似文献10.
Atsuhiko Toyoshima Takao Yasuhara Masahiro Kameda Jun Morimoto Hayato Takeuchi Feifei Wang Tatsuya Sasaki Susumu Sasada Aiko Shinko Takaaki Wakamori Mihoko Okazaki Akihiko Kondo Takashi Agari Cesario V. Borlongan Isao Date 《PloS one》2015,10(6)