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981.
Plummer PN Colson NJ Lewohl JM MacKay RK Fernandez F Haupt LM Griffiths LR 《Gene》2011,490(1-2):32-36
Migraine is a debilitating neurovascular disorder, with a substantial genetic component. The exact cause of a migraine attack is unknown; however cortical hyperexcitability is thought to play a role. As Gamma-aminobutyric Acid (GABA) is the major inhibitory neurotransmitter in the brain, malfunctioning of this system may be a cause of the hyperexcitability. To date, there has been limited research examining the gene expression or genetics of GABA receptors in relation to migraine. The aim of our study was to determine if GABA receptors play a role in migraine by investigating their gene expression using profile in migraine affected individuals and non-affected controls by Q-PCR. Gene expression of GABA(A) receptor subunit isoforms (GABRA3, GABRB3, GABRQ) and GABA(B) receptor 2 (GABBR2) was quantified in mRNA obtained from peripheral blood leukocytes from 28 migraine subjects and 22 healthy control subjects. Analysis of results showed that two of the tested genes, GABRA3 and GABBR2, were significantly down regulated in migraineurs (P=0.018; P=0.017), compared to controls. Results from the other tested genes did not show significant gene expression variation. The results indicate that there may be specific GABA receptor gene expression variation in migraine, particularly involving the GABRA3 and GABBR2 genes. This study also identifies GABRA3 and GABBR2 as potential biomarkers to select migraineurs that may be more responsive to GABA agonists with future investigations in this area warranted. 相似文献
982.
983.
Baragatti B Ciofini E Scebba F Angeloni D Sodini D Luin S Ratto GM Ottaviano V Pagni E Paolicchi A Nencioni S Coceani F 《American journal of physiology. Heart and circulatory physiology》2011,300(3):H892-H901
The fetal ductus arteriosus (DA) contracts to oxygen, and this feature, maturing through gestation, is considered important for its closure at birth. We have previously obtained evidence of the involvement of cytochrome P-450, possibly of the 3A subfamily (CYP3A), in oxygen sensing and have also identified endothelin (ET)-1 as the attendant effector for the contraction. Here, we examined comparatively wild-type (WT) and CYP3A-null (Cyp3a(-/-)) mice for direct validation of this concept. We found that the CYP3A subfamily is represented only by CYP3A13 in the WT DA. CYP3A13 was also detected in the DA by immunofluorescence microscopy, being primarily colocalized with the endoplasmic reticulum in both endothelial and muscle cells. However, a distinct signal was also evident in the plasma membrane. Isolated DAs from term WT animals developed a sustained contraction to oxygen with transient contractions superimposed. Conversely, no tonic response occurred in Cyp3a(-/-) DAs, whereas the phasic response persisted unabated. Oxygen did not contract the preterm WT DA but caused a full-fledged contraction after retinoic acid (RA) treatment. RA also promoted an oxygen contraction in the Cyp3a(-/-) DA. However, responses of RA-treated WT and Cyp3a(-/-) mice differed in that only the former abated with ET-1 suppression. This implies the existence of an alternative target for RA responsible for the oxygen-induced contraction in the absence of CYP3A13. In vivo, the DA was constricted in WT and Cyp3a(-/-) newborns, although with a tendency to be less narrowed in the mutant. We conclude that oxygen acts primarily through the complex CYP3A13 (sensor)/ET-1 (effector) and, in an accessory way, directly onto ET-1. However, even in the absence of CYP3A13, the DA may close postnatally thanks to the contribution of ET-1 and the likely involvement of compensating mechanism(s) identifiable with an alternative oxygen-sensing system and/or the withdrawal of relaxing influence(s) operating prenatally. 相似文献
984.
Ceconi C Comini L Suffredini S Stillitano F Bouly M Cerbai E Mugelli A Ferrari R 《American journal of physiology. Heart and circulatory physiology》2011,300(1):H366-H373
The aim of this study was to investigate the effect of chronic heart rate (HR) reduction with the hyperpolarization-activated current inhibitor ivabradine on the global phenotype of left ventricular (LV) remodeling in a ligated rat model. Seven days after coronary artery ligation, Wistar rats received ivabradine (10 mg · kg(-1) · day(-1) administered in drinking water) [myocardial infarction + ivabradine (MI+IVA), n = 22] or vehicle only (drinking water) (MI, n = 20) for 90 days. A sham group (n = 20) was included for model validation. MI+IVA rats had 12% lower HR (P < 0.01), improved LV volumes, 15% higher LV ejection fraction (LVEF, P < 0.01) than MI rats, and 33% reductions in both plasma atrial natriuretic peptide (ANP, P = 0.052) and cardiac hydroxyproline. Using patch-clamp, action potential duration was reduced and transient outward current density increased (P < 0.05). Cardiac energy metabolism was also improved (+33% creatine phosphate, P < 0.001; +15% ATP; and +9% energy charge, P < 0.05). Significant correlations were found between HR and parameters of cardiac metabolism, ANP, and LVEF (all P < 0.05). The HR-reducing properties of ivabradine prevent changes in the global phenotype of LV remodeling in the rat, optimize energy consumption, and avoid electrophysiological and structural remodeling. 相似文献
985.
Coiro V Volpi R Cataldo S Saccani-Jotti G Magotti MG Russo F Stella A Vignali A Chiodera P 《Regulatory peptides》2011,167(2-3):167-169
To evaluate the possible influence of idiopathic hyperprolactinemia on the arginine-vasopressin (AVP) response to osmotic and pressure-volumetric stimuli, 14 idiopathic hyperprolactinemic women and 13 normoprolactinemic women were studied during a hypertonic saline infusion test (0.51M NaCl infusion for 2h) and an orthostatic test (standing upright and maintaining an orthostatic position for 20min). In both experimental conditions, the AVP response was significantly higher in women with idiopathic hyperprolactinemia than in normal normoprolactinemic women. These results indicate that in women hyperprolactinemia influences the AVP response to hyperosmotic and hypovolemic stimuli. 相似文献
986.
987.
Sadiq I Fanucchi F Paparelli E Alpi E Bachi A Alpi A Perata P 《Journal of plant physiology》2011,168(18):2234-2243
Rice is the staple food for more than fifty percent of the world's population, and is therefore an important crop. However, its production is hindered by several biotic and abiotic stresses. Although rice is the only crop that can germinate even in the complete absence of oxygen (i.e. anoxia), flooding (low oxygen) is one of the major causes of reduced rice production. Rice germination under anoxia is characterized by the elongation of the coleoptile, but leaf growth is hampered. In this work, a comparative proteomic approach was used to detect and identify differentially expressed proteins in the anoxic rice coleoptile compared to the aerobic coleoptile. Thirty-one spots were successfully identified by MALDI-TOF MS analysis. The majority of the identified proteins were related to stress responses and redox metabolism. The expression levels of twenty-three proteins and their respective mRNAs were analyzed in a time course experiment. 相似文献
988.
Microorganisms play integral roles in the cycling of carbon (C) and nitrogen (N) in recirculating aquaculture systems (RAS) for fish and shellfish production. We quantified the pathways of shrimp fecal bacterial activities and their role in C- and N-flux partitioning relevant to culturing Pacific white shrimp, Penaeus (Litopenaeus) vannamei, in RAS. Freshly produced feces from P. vannamei contained 0.6-7 × 10(10) bacteria g(-1) dry wt belonging to Bacteroidetes (7%), Alphaproteobacteria (4%), and, within the Gammaproteobacteria, almost exclusively to the genus Vibrio (61%). Because of partial disintegration of the feces (up to 27% within 12 h), the experimental seawater became inoculated with fecal bacteria. Bacteria grew rapidly in the feces and in the seawater, and exhibited high levels of aminopeptidase, chitinase, chitobiase, alkaline phosphatase, α- and β-glucosidase, and lipase activities. Moreover, fecal bacteria enriched the protein content of the feces within 12 h, potentially enriching the feces for the coprophagous shrimp. The bacterial turnover time was much faster in feces (1-10 h) than in mature RAS water (350 h). Thus, shrimp fecal bacteria not only inoculate RAS water but also contribute to bacterial abundance and productivity, and regulate system processes important for shrimp health. 相似文献
989.
Stanniocalcin 1 (STC1) is a glycoprotein hormone expressed in different mammalian tissues. In previous studies, we showed STC1 expression in swine ovarian follicles and we demonstrated that STC1 may be a physiological regulator of follicular function. Since reactive oxygen species (ROS) are important signal transducers in the ovary, the present study was undertaken to investigate STC1 action on ROS generation and on the activity of the major enzymatic and non-enzymatic scavengers in swine granulosa cells. O(2)- generation, catalase activity and FRAP levels were increased by STC1, whereas H(2)O(2) generation and peroxidase activity were decreased by STC1. Taken together, our data show that STC1 modulates redox status in swine granulosa cells. 相似文献
990.
Plants contain three classes of hemoglobins which are not associated with nitrogen fixing bacteria, and have been accordingly termed nonsymbiotic hemoglobins. The function of nonsymbiotic hemoglobins is as yet mostly unknown. A NO dioxygenase activity has been proposed and demonstrated for some of them in vitro. In this context, a sound molecular mechanism that relates the structure with the biological activity is crucial to suggest a given physiological role. Insight into such a mechanism is now facilitated by recent progress made in both experimental and computational techniques. These studies have highlighted a number of key structural features implicated in the function of nonsymbiotic hemoglobins. The bis-histidyl hexacoordination of the heme in both its ferric and ferrous states provides a powerful and general tool to modulate reactivity, protein dynamics, and shape of the cavities. In addition, the specific arrangement of distal cavity residues provides effective protection against autoxidation. Inspection of the static crystal structures available for both liganded and unliganded states seems unsufficient to explain the function of these proteins. Function appears to be intimately linked with protein flexibility, which influences the dynamical behavior of inner cavities, capable of delivering apolar reactants to the reaction site, and removing charged reaction products. In this mini review, we demonstrate how the integration of information derived from experimental assays and computational studies is valuable and can shed light into the linkage between structural plasticity of nonsymbiotic hemoglobins and their biological role. 相似文献