Fetal life evolves in a hypoxic environment. Changes in the oxygen content in utero caused by conditions such as pre-eclampsia or type I diabetes or by oxygen supplementation to the mother lead to increased free radical production and correlate with perinatal outcomes. In the fetal-to-neonatal transition asphyxia is characterized by intermittent periods of hypoxia ischemia that may evolve to hy...

Experiments were designed to test the hypothesis that endothelin (ET) and/or reactive oxygen species contribute to the pressor response induced by acute air jet stress in normotensive Dahl salt-sensitive rats maintained on a normal salt diet (prehypertensive). Mean arterial pressure was chronically monitored by telemetry before and after 3-day treatment with the free radical scavenger 4-hydroxy...

The reactivity hypothesis postulates that large magnitude cardiovascular reactions to psychological stress contribute to the development of pathology. A key but little tested assumption is that such reactions are metabolically exaggerated. Cardiac activity, using Doppler echocardiography, and oxygen consumption, using mass spectrometry, were measured at rest and during and after a mental stress...

The aim of this study was to investigate the effects of acute and repeated immobilization stress on oxygen consumption of the isolated interstitial rats' testes cells (ISC). The ISC testes cells were isolated acording to Anakwe et al. The oxygen consumption by ISC testes was measured polarographically in vitro with a Clark-type oxygen electrode (YSI-5331, Yellow Springs Instrument), which was d...

BACKGROUND Reactive oxygen species arise in the mitochondria as byproducts of respiration and oxidase activity and have important roles in many physiological and pathophysiological conditions. The level of reactive oxygen species is regulated by a number of enzymes and physiological antioxidants, including HO-1, Sod2, catalase and COX-2, etc. And HO-1 against oxidative stress requires an increa...

Reactive oxygen species (ROS) play a key role in the acclimation process of plants to abiotic stress. They primarily function as signal transduction molecules that regulate different pathways during plant acclimation to stress, but are also toxic byproducts of stress metabolism. Because each subcellular compartment in plants contains its own set of ROS-producing and ROS-scavenging pathways, the...

Formation of small and highly reactive oxygen species (ROS) is normal phenomena in living cells. The Reactive Oxygen Species cover free radical such as superoxide (O2 ̅ ), hydroxyl (OH), perhydroxy (HO2 ̅ ) and alkoxy (RO) and non-radicals like, hydrogen peroxide (H2O2) and singlet oxygen ( O2). Their formation and reactivity is well established and found to be tightly regulated. ROS level exceed...