Mice deficient in the transcription factor Pet-1⁻/⁻ have a ∼70% deficiency of brainstem serotonin [5-hydroxytryptamine (5-HT)] neurons and exhibit spontaneous bradycardias in room air at postnatal day (P)5 and P12 and delayed gasping in response to a single episode of anoxia at P4.5 and P9.5 (Cummings KJ, Li A, Deneris ES, Nattie EE. Am J Physiol Regul Integr Comp Physiol 298: R1333-R1342, 2010...

AIM To study the effects of tetrandrine (Tet) on the changes of NMDA receptor channels in cortical neurons induced by anoxia. METHODS Cell-attached configuration of patch-clamp techniques. Anoxia was produced by perfused cells with 95% N2 + 5% CO2 gassed bath solution. RESULTS During anoxia, the open time constant (tau 2), open probability (Po) of 35-pS and 100-pS channels increased. Tet 7....

The effects of anoxia on intracellular pH (pH(i)) were examined in acutely isolated adult rat hippocampal CA1 neurons loaded with the H(+)-sensitive fluorophore, 2',7'-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein. During perfusion with HCO/CO(2)- or HEPES-buffered media (pH 7.35) at 37 degrees C, 5- or 10-min anoxic insults were typified by an intracellular acidification on the induction o...

The effects of ischemia and anoxia on cardiac adenosine 3',5'-monophosphate (cyclic AMP) concentration, glycogen phosphorylase activity ratio (— 5'-AMP: + 5'-AMP), phosphorylase kinase activity ratio (pH 6.8:8.2), and myocardial contractility (left ventricular dP/dt) were studied in an open-chest rat heart preparation. Ischemia produced by termination of coronary blood flow increased cyclic AMP...

It has been established that adenosine has a critical role in the extraordinary ability of the turtle brain to survive anoxia. To further investigate this phenomenon we compared rat and turtle brain adenosine A1receptors using cyclopentyl-1,3-dipropylxanthine,8-[dipropyl-2,3-3H(N)] ([3H]DPCPX) saturation binding analyses and determined the effects of prolonged anoxia (6, 12, and 24 h) on the ad...

Oxygen deprivation is rapidly deleterious for most organisms. However, Caenorhabditis elegans has developed the ability to survive anoxia for at least 48 hours. Mutations in the DAF-2/DAF-16 insulin-like signaling pathway promote such survival. We describe a pathway involving the HYL-2 ceramide synthase that acts independently of DAF-2. Loss of the ceramide synthase gene hyl-2 results in increa...

The responses to anoxia and acidosis of cardiac ventricular muscle strips from the anoxia-tolerant turtle Chrysemys picta bellii were investigated at 10 degrees C and 20 degrees C. Force-velocity curves were determined by quick isotonic releases at 85% of the time to peak isometric force under control, anoxia, lactate acidosis and anoxic lactate acidosis conditions. The isotonic forces during q...

Individuals with type 2 diabetes display metabolic abnormalities, such as hyperglycemia, increased free fatty acids, insulin resistance, and altered ceramide levels, that contribute to vascular dysfunctions and compromised oxygen delivery. Caenorhabditis elegans fed a glucose-supplemented diet or with altered ceramide metabolism, due to a hyl-2 mutation, are sensitive to oxygen deprivation (ano...

Survival of brain anoxia during months of winter dormancy by the Western painted turtle, Chrysemys picta, may rely on inactivation of neuronal ion channels. During 2 h of anoxia, Ca2+ influx via the N-methyl-d-aspartate (NMDA) subtype of glutamate receptor decreases 30-40%, but it is not known if prolonged anoxic dormancy is associated with even more profound downregulation of this important ch...

Running head : Effects of anoxia and aglycaemia on neuronal [Ca 2+ ] i. ABSTRACT Nociceptive neurons play an important role in ischemia by sensing and transmitting information to the CNS and by secreting peptides and nitric oxide which can have local effects. Whilst these responses are probably primarily mediated by acid sensing channels other events occurring in ischemia may also influence neu...