The role of pH on the calcium dependence of nitric oxide synthase (NOS) of Cyprinus carpio brain was investigated. This fish is known to survive prolonged periods of hypoxia. Under this condition, cerebral blood flow is no longer regulated by nitric oxide (NO). Nitric oxide synthase activity is pH dependent in the range of pH between 7.4 and 6.2 with a decrease when tissue acidifies. At acidic pH, the dependence of the NOS activity on the free Ca2+ concentrations changes considerably and shows an EC50 of 0.13 muM at pH 7.1 and of 5.1 muM at pH 6.2 for the soluble enzyme. The variation in the Ca2+ dependence with acidification is greater for the soluble than for the particulate enzyme. This may be the main factor protecting sudden NO formation mainly during anoxic-normoxic transitions.

Role of pH on the calcium ion dependence of the nitric oxide synthase in the carp brain / Conte, Angela. - In: BRAIN RESEARCH BULLETIN. - ISSN 0361-9230. - STAMPA. - 56:1(2001), pp. 67-71. [10.1016/S0361-9230(01)00604-9]

Role of pH on the calcium ion dependence of the nitric oxide synthase in the carp brain

CONTE, Angela
2001

Abstract

The role of pH on the calcium dependence of nitric oxide synthase (NOS) of Cyprinus carpio brain was investigated. This fish is known to survive prolonged periods of hypoxia. Under this condition, cerebral blood flow is no longer regulated by nitric oxide (NO). Nitric oxide synthase activity is pH dependent in the range of pH between 7.4 and 6.2 with a decrease when tissue acidifies. At acidic pH, the dependence of the NOS activity on the free Ca2+ concentrations changes considerably and shows an EC50 of 0.13 muM at pH 7.1 and of 5.1 muM at pH 6.2 for the soluble enzyme. The variation in the Ca2+ dependence with acidification is greater for the soluble than for the particulate enzyme. This may be the main factor protecting sudden NO formation mainly during anoxic-normoxic transitions.
2001
56
1
67
71
Role of pH on the calcium ion dependence of the nitric oxide synthase in the carp brain / Conte, Angela. - In: BRAIN RESEARCH BULLETIN. - ISSN 0361-9230. - STAMPA. - 56:1(2001), pp. 67-71. [10.1016/S0361-9230(01)00604-9]
Conte, Angela
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Licenza Creative Commons
I metadati presenti in IRIS UNIMORE sono rilasciati con licenza Creative Commons CC0 1.0 Universal, mentre i file delle pubblicazioni sono rilasciati con licenza Attribuzione 4.0 Internazionale (CC BY 4.0), salvo diversa indicazione.
In caso di violazione di copyright, contattare Supporto Iris

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11380/304608
Citazioni
  • ???jsp.display-item.citation.pmc??? 2
  • Scopus 8
  • ???jsp.display-item.citation.isi??? 8
social impact