Carbon Monoxide as an Attenuator of Vasoconstriction in Piglet Cerebral Arterioles1
| Autor: | John S. Winestone, Clarissia Bonner, Charles W. Leffler |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
Mean arterial pressure
medicine.medical_specialty Platelet-activating factor medicine.disease General Biochemistry Genetics and Molecular Biology 030218 nuclear medicine & medical imaging Heme oxygenase 03 medical and health sciences chemistry.chemical_compound Cerebral circulation 0302 clinical medicine Blood pressure Endocrinology Hypocapnia chemistry Anesthesia Dilator Internal medicine cardiovascular system medicine medicine.symptom 030217 neurology & neurosurgery Vasoconstriction circulatory and respiratory physiology |
| Zdroj: | Experimental Biology and Medicine. 228:46-50 |
| ISSN: | 1535-3699 1535-3702 |
| DOI: | 10.1177/153537020322800106 |
| Popis: | Carbon monoxide (CO) is an endogenous dilator in the newborn cerebral circulation. The present study addressed the hypothesis that endogenous CO attenuates pial arteriolar vasoconstriction caused by hypocapnia, platelet activating factor, and elevated blood pressure. Experiments used anesthetized piglets with implanted, closed cranial windows. Topical application of a metal porphyrin inhibitor of heme oxygenase was used to inhibit production of CO. Chromium mesopophyrin increased vasoconstriction in response to hypocapnia. The constrictor response to a topical stimulus, platelet activating factor, was also increased by application of chromium mesoporphyrin. Inhibition of heme oxygenase did not constrict pial arterioles in normotensive newborn pigs (mean arterial pressure of about 70 mmHg), but did constrict pial arterioles of piglets with experimentally induced increases in arterial pressure (mean arterial pressure greater than 90 mmHg). In fact, pial arterioles of normotensive piglets transiently dilated to chromium mesoporphyrin, whereas those of hypertensive piglets progressively constricted during 10 min of chromium mesoporphyrin treatment. Therefore, inhibition of heme oxygenase augments cerebral vasoconstriction in response to several very different constrictor stimuli. These data suggest endogenous CO attenuates vasoconstrictor responses in the newborn cerebral circulation. |
| Databáze: | OpenAIRE |
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