423 ABSTRACT Moderate elevations of nitrite and nitric oxide (NO) protect mammalian tissues against ischemia (anoxia)-reperfusion damage by inhibiting mitochondrial electron transport complexes and reducing the formation of reactive oxygen species (ROS) upon reoxygenation. Crucian carp appear to exploit this mechanism by upregulating nitrite and other nitrite/NO metabolites (S-nitroso and iron-...

The crucian carp (Carassius carassius L.) is one of the most anoxia-tolerant vertebrates known, being able to maintain ion homeostasis in its brain for many hours of anoxia. This study aims to clarify the importance of glycolysis during anoxia and also to investigate whether the extreme tolerance to anoxia could be due to down-regulation of K+ permeability ('channel arrest') and/or activation o...

It is well known from various mammalian cells that anoxia has a major impact on the mitogen-activated protein kinase ERK, but a possible similar effect in fish cells has not been investigated. Here we characterise a p44ERK-like protein in the rainbow trout cell line RTHDF and study the effect of (i) serum stimulation, (ii) sodium azide (chemical anoxia) and removal of azide (recovery) and (iii)...

Crucian carp is one of few vertebrates that tolerate anoxia. It maintains brain ATP during anoxia partially by reducing ATP consumption. However, unlike turtles, which become comatose during anoxia, this fish remains physically active. This striking difference in anoxic survival strategy is reflected all the way down to the cellular level.

Holometabolous insects undergo dramatic morphological and physiological changes during ontogeny. In particular, the larvae of many holometabolous insects are specialized to feed in soil, water or dung, inside plant structures, or inside other organisms as parasites where they may commonly experience hypoxia or anoxia. In contrast, holometabolous adults usually are winged and live with access to...

BACKGROUND Paraoxonase 1 (PON1) is a protein found associated with high density lipoprotein (HDL), thought to prevent oxidative modification of low-density lipoprotein (LDL). This enzyme has been implicated in lowering the risk of cardiovascular disease. Anoxia-reoxygenation and oxidative stress are important elements in cardiovascular and cerebrovascular disease. However, the role of PON1 in a...

Contrary to what is found in most vertebrates, the brains of certain turtle species maintain ATP levels and ion homeostasis and survive prolonged anoxia. The hypothesis tested here is that the release of adenosine and its binding to A1 receptors are essential for this anoxic tolerance. Studies were conducted in the isolated turtle cerebellum, which did release adenosine to the extracellular spa...

The effect of anoxia and reoxygenation on the synthesis and secretion of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) was studied in primary cultures of human umbilical vein endothelial cells. Sublethal anoxia, determined by trypan blue dye exclusion and lactate dehydrogenase release, was produced by cell culture under a 95% N2, 5% CO2 atmosphere for 2-...

Rice coleoptiles, renowned for anoxia tolerance, were hypoxically pretreated, excised, 'healed', and then exposed to a combination of anoxia and pH 3.5. The putative acid load was confirmed by net effluxes of K(+) to the medium, with concurrent net decreases of H(+) in the medium, presumably mainly due to H(+) influx. Yet the coleoptiles survived the combination of anoxia and pH 3.5 for at leas...

Heat shock proteins (HSPs) may play a cardioprotective role during hypoxia or ischemia. We hypothesized that cardiac tissue from hypoxia-tolerant animals might have high levels of specific HSPs. We measured myocardial HSP60 and HSP72/73 in painted and softshell turtles during normoxia and anoxia (12 h) and after recovery (12 or 24 h). We also measured myocardial HSPs in normoxic rats and rabbit...