26 research outputs found
Effects of sodium bicarbonate on lactate levels during supramaximal exercise
Aerobically trained females (n=15) performed 4 supramax exercise bouts 1 hr after orally ingesting either 200 mg/kg body wt. NaHCO3 or 5.0 g. NaC1, to determine the effects of NaHCO3 on blood lactate concentration. Using a double blind protocol, each S performed 4 randomized conditions: 1) NaC1-30 sec, 2) NaC1-time to exhaustion (TTE), 3) NaHCO3-30 sec, 4) NaHCO3-TTE. The Wingate Anaerobic Test was used to elicit supramax exercise. 4 ml samples of blood were drawn from the antecubital vein 30 min post-ingestion and 5 min post-exercise in each of the 4 conditions. Lactic acid (LA) was determined using the enzymatic method described by Sigma Chemical Co. (1977). Pedal revolutions were recorded for determination of total work (TW). Statistical analysis of the data revealed no sig (p > .05) diff in TW, post-ingestion LA, NaHCO3 (7 mg%), NaC1 (6 mg%), and TTE-LA, NaHCO3 (88 mg%), NaC1 (81 mg%). However, in the 30 sec trial, LA levels were sig (p < .05) higher with NaHCO3 (73 mg%), than NaC1 (62 mg%). This increased LA with NaHCO3 was attributed to improved efflux of LA across the sarcolemma. The explanation for no sig diff in TTE-LA was unclear, perhaps an error in test protocol. Based on these results, it appears that while NaHCO3 may improve efflux of LA, it does not improve performance in short-term supramax exercise
Superficial thrombophlebitis of the abdominal veins as a complication of ruptured aortocaval fistula surgery
CLINICO - HAEMATOLOGICAL PROFILE AND OUTCOME OF CEREBRAL MALARIA IN A TEACHING HOSPITAL OF SOUTH EAST RAJASTHAN
The relative importance of N-oxidation and N-demethylation in the metabolism of trimethylamine in man
Regulated Deficit Irrigation as a Water-Saving Strategy for Onion Cultivation in Mediterranean Conditions
Gender differences in the mechanism of dioxin toxicity in rodents and in nonhuman primates
Evidence that C-terminal non-kinase domain of Pbs2p has a role in high osmolarity-induced nuclear localization of Hog1p
Acid-base profile of healthy mongrel Indian Familaris canis determined by different techniques under two non-volatile anaesthetics
Neuronal hyperactivity accelerates depletion of neural stem cells and impairs hippocampal neurogenesis
Adult hippocampal neurogenesis is believed to maintain a range of cognitive functions, many of which decline with age. We recently reported that radial neural stem cells (rNSCs) in the hippocampus undergo activation-dependent conversion into astrocytes, a mechanism that over time contributes to a reduction in the rNSC population. Here, we injected low and high levels of kainic acid (KA) in the dentate gyrus to assess whether neuronal hyperexcitation, a hallmark of epileptic disorders, could accelerate this conversion. At low levels of KA, generating epileptiform activity without seizures, we indeed found increased rNSC activation and conversion into astrocytes. At high levels, generating sustained epileptic seizures, however, we find that rNSCs divide symmetrically and that both mother and daughter cells convert into reactive astrocytes. Our results demonstrate that a threshold response for neuronal hyperexcitation provokes a dramatic shift in rNSC function, which impairs adult hippocampal neurogenesis in the long term.publisher: Elsevier
articletitle: Neuronal Hyperactivity Accelerates Depletion of Neural Stem Cells and Impairs Hippocampal Neurogenesis
journaltitle: Cell Stem Cell
articlelink: http://dx.doi.org/10.1016/j.stem.2015.04.003
associatedlink: http://dx.doi.org/10.1016/j.stem.2015.04.011
content_type: article
copyright: Copyright © 2015 Elsevier Inc. All rights reserved.status: publishe