The Effect of Induced Hypothermia Upon Oxygen Consumption in the Rat Brain

Hägerdal, M.; Harp, James R.; Nilsson, L.; Siesjou, B. K.

doi:10.1111/j.1471-4159.1975.tb11881.x

Cited by 251 publications

(95 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…At the 16-min recirculation point, the serum arterial glucose concentration in the hypo thermic group was elevated (p < 0.05) compared to the hyperthermic and normothermic groups. Ele vated glucose concentration in the hypothermic groups is consistent with data reported by other in vestigators (Wynn, 1954(Wynn, , 1956Hagerdal et al, 1975). Intragroup comparisons of physiological data revealed few significant differences from control values for each group, except for hyperthermic ar terial pH, which was consistently acidotic during the recirculation period.…”

Section: Resultssupporting

confidence: 89%

The Metabolic Effects of Mild Hypothermia on Global Cerebral Ischemia and Recirculation in the Cat: Comparison to Normothermia and Hyperthermia

Chopp

Knight

Tidwell

et al. 1989

J Cereb Blood Flow Metab

219

View full text Add to dashboard Cite

Summary:The metabolic effects of graded whole body hypothermia on complete global cerebral ischemia and recirculation was investigated in the cat. Hypothermia was induced to one of three levels prior to ischemia; T = 26.8° ± OSC (n = 4), T = 32.1° ± 0.2°C (n = 5), and T = 34.6° ± 0.3°C (n = 6), and maintained constant throughout 16 min of ischemia and 1.5-2 h of recircula tion. Intracellular cerebral pH and relative concentrations of high-energy phosphate metabolites were continuously monitored, using in vivo 31p nuclear magnetic resonance (NMR) spectroscopy. Except for the first 4 min of isch emia, no significant differences were detected in the re sponse of adenylate intensities and intracellular pH to ischemia and recirculation between the hypothermic groups. The three hypothermic groups were then pooledThe effect of whole body hypothermia on cere bral metabolism has a long history (Field et aI., 1944). The possible beneficial effects of hypother mia on cerebral pathophysiological conditions have also been explored (see Siesj6, 1978). Whole body hypothermia, when applied judiciously, can curtail metabolic changes and lessen cerebral edema and neuropathologic damage associated with hypoxia (Carlsson et aI., 1976;Rosomoff 1959), and head injury (Shapiro et aI., 1974 141into one group, and the data compared to previously pub lished data from a normothermic group, T = 38.4° ± 0.6°C (n = 14), and a hyperthermic group, T = 40.6° ± 0.2°C (n = 9), subjected to the identical ischemic and NMR measurement protocols. The hypothermic animals exhibited a statistically significant reduction of cerebral intracellular acidosis, both during ischemia and recircu lation, as well as a more rapid return of adenylate inten sities during recirculation, compared to the normothermic or hyperthermic groups. The data thus suggest that mild hypothermia has an ameliorative affect on brain energy metabolism and intracellular pH under conditions of com plete global cerebral ischemia and recirculation. Key Words: 31p NMR spectroscopy-Cerebral ischemia Hypothermia-Body temperature, and cerebral ischemia. emia, including circulatory arrest, with recircula tion (Marshal et aI., 1956; Kramer et aI., 1968; Ber ing, 1974; Perna et aI., 1973; Wolin et aI., 1973;Hickey, 1985) and without recirculation (Stocker et aI., 1986); the isolated perfused brain (Norwood et aI., 1979); and focal cerebral ischemia (Simeone et aI., 1979;Rosomoff, 1957). These studies, which were performed at temperatures below 30°C, sug gest that hypothermia results in a reduction in the rate of degradation of brain energy metabolism dur ing the onset of hypothermic ischemia as well as a reduced level of brain tissue acidosis compared with normothermic ischemia. However, the clinical application of hypothermia is limited by adverse ef fects associated with level as well as the duration of hypothermia (Popovic, 1960;Michenfelder and Milde, 1977;Bjork and Hultquist, 1960; Brunberg et aI., 1974; Connolly et aI., 1962; Olesen et aI., 1971).

show abstract

Section: Resultssupporting

confidence: 89%

The Metabolic Effects of Mild Hypothermia on Global Cerebral Ischemia and Recirculation in the Cat: Comparison to Normothermia and Hyperthermia

Chopp

Knight

Tidwell

et al. 1989

J Cereb Blood Flow Metab

219

View full text Add to dashboard Cite

show abstract

“…A lowering of the body temperature will reduce the general metabolism by about 5% per centigrade temperature decrease, 26 resulting in diminished O 2 -consumption. 24 The cardiac output is reduced in a linear fashion, but the MABP is less a ected in the temperature range between 38 to 308C. 41 This is probably achieved by a general vasoconstriction 27 and increased blood viscosity.…”

Section: Discussionmentioning

confidence: 99%

Spinal cord blood flow changes following systemic hypothermia and spinal cord compression injury: an experimental study in the rat using Laser-Doppler flowmetry

et al. 2001

View full text Add to dashboard Cite

Study design: It is well known that changes of the body temperature as well as trauma in¯uence the blood¯ow in the brain and spinal cord. However, there is still a lack of knowledge concerning the levels of blood¯ow changes, especially during hypothermia. Objectives: This investigation was carried out to examine the e ects of systemic hypothermia and trauma on spinal cord blood¯ow (SCBF). Methods: Twenty-four rats were randomized either to thoracic laminectomy only (Th VII ± IX) or to 35 g spinal cord compression trauma. The animals were further randomized to either constant normothermia (388C) or to a systemic cooling procedure, ie reduction of the esophageal temperature from 38 to 308C. SCBF was recorded 5 mm caudal to the injury zone using Laser-Doppler¯owmetry which allows a non-invasive continuous recording of local changes in the blood¯ow. The autoregulation ability was tested at the end of the experiments by inducing a 30 ± 50 mmHg blood-pressure fall, using blood-withdrawal from the carotid artery. Results: The mean SCBF decreased 2.8% and 3.5% per centigrade reduction of esophageal temperature in the animals sustained to hypothermia with and without trauma, respectively. This could be compared to a decrease of 0.2%/min when only trauma was applied. No signi®cant di erences were seen between the groups concerning auto regulatory ability. Conclusions: Our results indicate that the core temperature has a high impact on the SCBF independent of previous trauma recorded by Laser-Doppler¯owmetry. This in¯uence exceeds the response mediated by moderate compression trauma alone. Sponsorship: The study was supported by grants from the Laerdal foundation. Spinal Cord (2001) 39, 74 ± 84

show abstract

“…Hypothermia is known to protect animals from hypox ia (15 17). The protective effects of hypothermia against hypoxia are thought to involve decreases in brain meta bolic rate and increased affinity of hemoglobin for oxygen (23,24). Namely, under hypoxic conditions, the levels of …”

Section: Discussionmentioning

confidence: 99%

Protection by Disulfiram and Diethyldithiocarbamate against Hypoxia-Induced Lethality in Mice

Masukawa

Nakanishi

1993

Japanese Journal of Pharmacology

View full text Add to dashboard Cite

ABSTRACT-The effects of disulfiram (DS) and its major metabolite, diethyldithiocarbamate (DEDC), on the survival time under normobaric and hypobaric hypoxia were examined in mice. At an ambient temperature of 241C, DS at 0.5 3.0 mmol/kg (i.p.) caused a marked dose-dependent prolongation of the survival time in mice subjected to both types of hypoxia. DEDC also prolonged the survival time, but the effect was less at its higher doses which decreased brain superoxide dismutase. The maximum effects of DS and DEDC were found at 3 hr and 1 hr after injection, respectively. Of the metabolites of DEDC, the cop per complex with DEDC caused a significant effect, whereas neither diethylamine nor carbon disulfide did. Furthermore, DS, DEDC and copper complex caused marked hypothermia, and the time course changes of hypothermia by DS and DEDC closely paralleled those of the degree of anti-hypoxic effects, respectively. At an ambient temperature of 361C, in which the body temperature was maintained near the normal level, both DS and DEDC still exhibited a weak anti-hypoxic effect. These results suggest that DEDC itself, formed as a metabolite of DS, and partly the copper complex produced the anti-hypoxic effect, which could not be ex plained by concomitant hypothermia alone.Keywords: Disulfiram, Diethyldithiocarbamate, Hypoxia-induced lethality, Ambient temperature, Superoxide dismutase (brain)The disulfide disulfiram (DS) is rapidly converted in vivo into two molecules of diethyldithiocarbamate (DEDC), its corresponding thiol, which is subsequently further biotransformed (1-4). The former compound is in current usage in alcohol aversion therapy, and the lat ter compound is a potent chelator of copper and can in hibit various copper-containing enzymes such as superox ide dismutase (SOD) both in vitro and in vivo (5). DEDC is well known to exhibit a protective effect against liver in jury induced by various hepatotoxins, and its effect was as sumed to be based on inhibition of the mixed-function ox idase system, which activated the hepatotoxins to toxic metabolites (6 8). Furthermore, there were many reports dealing with the influence of DS and DEDC on oxygen toxicity in lungs and brain, although the results were different among investigators (9-13). However, there has been no information on the effects of DEDC and DS on hypoxic injury.In the present study, we investigated the influences of DEDC and DS on cerebral hypoxic injury using a hypoxic mouse model, in which the survival time was measured in mice exposed to hypoxia. MATERIALS AND METHODSChemicals and animals DS, DEDC, diethylamine and carbon disulfide were obtained from Wako Pure Chemical Industries, Osaka.(DEDC)2Cu, (DEDC)2Zn and (DEDC)3Fe were from Tokyo Kasei Kogyo Co., Ltd., Tokyo. Other reagents used were of analytical grade. The animals used were male ICR mice weighing about 30 g (5 to 6-week-old) and were obtained from Japan SLC, Inc., Hamamatsu. They were housed on a 12-hr light-dark cycle (light 7:00-19:00 hr) with food and water freely available. The experime...

show abstract

The Effect of Induced Hypothermia Upon Oxygen Consumption in the Rat Brain

Cited by 251 publications

References 14 publications

The Metabolic Effects of Mild Hypothermia on Global Cerebral Ischemia and Recirculation in the Cat: Comparison to Normothermia and Hyperthermia

The Metabolic Effects of Mild Hypothermia on Global Cerebral Ischemia and Recirculation in the Cat: Comparison to Normothermia and Hyperthermia

Spinal cord blood flow changes following systemic hypothermia and spinal cord compression injury: an experimental study in the rat using Laser-Doppler flowmetry

Protection by Disulfiram and Diethyldithiocarbamate against Hypoxia-Induced Lethality in Mice

Contact Info

Product

Resources

About