Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085383 (hypocapnia)
 1,697 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have previously demonstrated a 40% increase in myocardial blood flow (MBF) during hypercapnia but no significant decrease of MBF during hypocapnia. The present study was undertaken to evaluate if epinephrine infusion, which increases both myocardial oxygen consumption (MVo2) and myocardial performance, might influence the effects of hypocapnia and hypercapnia on MBF. Induction of hypocapnia was performed by hyperventilation in closed-chest dogs anesthetized with pentobarbital. By adding carbon dioxide to the inspiratory gas, normocapnia and hypercapnia were created. Epinephrine infusion (0.8 microgram X kg-1 X min-1) increased MBF and cardiac output (CO) by 90 and 140%, respectively, while MVo2 was increased by 45%. Epinephrine had a direct coronary vasodilating effect in excess of myocardial needs evidenced by increased oxygen content of the coronary sinus blood. During epinephrine infusion, induction of hypocapnia effected no change of MBF, while myocardial oxygen extraction increased significantly. Although oxygen saturation (So2) and Po2 in the coronary sinus blood decreased, these values remained well above those with hypocapnia without epinephrine infusion, thereby excluding impaired oxygen supply to the heart. Hypercapnia induced an increase of MBF by nearly 40% despite the coronary vasodilatation already induced by epinephrine infusion.
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PMID:Effects of hypo- and hyper-capnia on myocardial blood flow and metabolism during epinephrine infusion in the dog. 308

The authors of this article studied the influence of hypoxia, on thirteen groups of male rats, at altitudes of 2 200 m; 5 000 m; and 8 000 m assimilated in a barochamber by chronic or acute exposure (from 2 hours to 21 days) upon the parameters of acid-base equilibrium. The data obtained demonstrated the development of gaseous alkalosis, which is directly proportional to the altitude and time of exposure, hypocapnia, a decrease in excess base and actual bicarbonate, as well as decreased in oxygen pressure. Adrenalin and noradrenalin administered intraperitoneally produced an acidotic effect. Adrenalectomized animals exposed to hypoxia developed mixed alkalosis-respiratory and metabolic reaction.
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PMID:A study of acid-base equilibrium in altitudinal hypoxia. 392 88