Endogenous preoptic hydrogen sulphide attenuates hypoxia-induced hyperventilation.

We hypothesized that hydrogen sulphide (H2 S), acting specifically in the anteroventral preoptic region (AVPO - an important integrating site of thermal and cardiorespiratory responses to hypoxia in which H2 S synthesis has been shown to be increased under hypoxic conditions), modulates the hypoxic ventilatory response.
To test this hypothesis, we measured pulmonary ventilation (V˙E) and deep body temperature of rats before and after intracerebroventricular (icv) or intra-AVPO microinjection of aminooxyacetate (AOA; CBS inhibitor) or Na2 S (H2 S donor) followed by 60 min of hypoxia exposure (7% O2 ). Furthermore, we assessed the AVPO levels of H2 S of rats exposed to hypoxia. Control rats were kept under normoxia.
Microinjection of vehicle, AOA or Na2 S did not change V˙E under normoxic conditions. Hypoxia caused an increase in ventilation, which was potentiated by microinjection of AOA because of a further augmented tidal volume. Conversely, treatment with Na2 S significantly attenuated this response. The in vivo H2 S data indicated that during hypoxia the lower the deep body temperature the smaller the degree of hyperventilation. Under hypoxia, H2 S production was found to be increased in the AVPO, indicating that its production is responsive to hypoxia. The CBS inhibitor attenuated the hypoxia-induced increase in the H2 S synthesis, suggesting an endogenous synthesis of the gas.
These data provide solid evidence that AVPO H2 S production is stimulated by hypoxia, and this gaseous messenger exerts an inhibitory modulation of the hypoxic ventilatory response. It is probable that the H2 S modulation of hypoxia-induced hyperventilation is at least in part in proportion to metabolism.
AuthorsM Kwiatkoski, R N Soriano, G S F da Silva, H D Francescato, T M Coimbra, M L Glass, E C Carnio, L G S Branco
JournalActa physiologica (Oxford, England) (Acta Physiol (Oxf)) Vol. 210 Issue 4 Pg. 913-27 (Apr 2014) ISSN: 1748-1716 [Electronic] England
PMID24119224 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Copyright© 2013 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.
Chemical References
  • Aminooxyacetic Acid
  • Hydrogen Sulfide
  • Aminooxyacetic Acid (administration & dosage, pharmacology)
  • Animals
  • Anoxia (complications)
  • Hydrogen Sulfide (administration & dosage, pharmacology)
  • Hyperventilation (metabolism)
  • Male
  • Preoptic Area
  • Rats
  • Rats, Wistar

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research network!

Choose Username:
Verify Password: