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(Referência obtida automaticamente do SciELO, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Carbon monoxide: from toxin to endogenous modulator of cardiovascular functions

Texto completo
Autor(es):
R.A. Johnson [1] ; F. Kozma [2] ; E. Colombari [3]
Número total de Autores: 3
Afiliação do(s) autor(es):
[1] Universidade Federal de São Paulo
[2] Semmelweis University of Medicine
[3] Universidade Federal de São Paulo
Número total de Afiliações: 3
Tipo de documento: Artigo Científico
Fonte: Brazilian Journal of Medical and Biological Research; v. 32, n. 1 1999-01-00.
Resumo

Carbon monoxide (CO) is a pollutant commonly recognized for its toxicological attributes, including CNS and cardiovascular effects. But CO is also formed endogenously in mammalian tissues. Endogenously formed CO normally arises from heme degradation in a reaction catalyzed by heme oxygenase. While inhibitors of endogenous CO production can raise arterial pressure, heme loading can enhance CO production and lead to vasodepression. Both central and peripheral tissues possess heme oxygenases and generate CO from heme, but the inability of heme substrate to cross the blood brain barrier suggests the CNS heme-heme oxygenase-CO system may be independent of the periphery. In the CNS, CO apparently acts in the nucleus tractus solitarii (NTS) promoting changes in glutamatergic neurotransmission and lowering blood pressure. At the periphery, the heme-heme oxygenase-CO system can affect cardiovascular functions in a two-fold manner; specifically: 1) heme-derived CO generated within vascular smooth muscle (VSM) can promote vasodilation, but 2) its actions on the endothelium apparently can promote vasoconstriction. Thus, it seems reasonable that the CNS-, VSM- and endothelial-dependent actions of the heme-heme oxygenase-CO system may all affect cardiac output and vascular resistance, and subsequently blood pressure. (AU)

Processo FAPESP: 97/10415-9 - Robert Alan Johnson | New York Medical College - Estados Unidos
Beneficiário:Eduardo Colombari
Modalidade de apoio: Auxílio à Pesquisa - Pesquisador Visitante - Internacional