Hypoxia: Breathe easy

Hypoxia, the lack of oxygen at the tissue level of the body despite adequate blood flow, is commonly associated with high altitudes but also occurs in patients with breathing disorders. The physiological response to hypoxia is an increase in respiration, and Lipton et al. now describe a biochemical mechanism that can explain this response. Haemoglobin deoxygenation causes an increase in ventilation via S-nitrosothiols. In particular, S-nitrosoglutathione (GSNO) stereoselectively stimulates the brainstem ventilatory response to hypoxia. This finding has immediate therapeutic implications for disorders such as sleep-associated breathing irregularities.

S-Nitrosothiols signal the ventilatory response to hypoxia
ANDREW J. LIPTON, MICHAEL A. JOHNSON, TIMOTHY MACDONALD, MICHAEL W. LIEBERMAN, DAVID GOZAL & BENJAMIN GASTON
Nature 413, 171–174 (13 September 2001)
| First Paragraph | Full Text | PDF (223 K) |

Physiology: Nitric oxide and respiration
STUART A. LIPTON
The theory that haemoglobin evolved to carry oxygen around the body may need a rethink in light of another way in which molecules related to nitric oxide, released from haemoglobin, help the brain control respiration.
Nature 413, 118–121 (13 September 2001)
| Full Text | PDF (144 K) |

SNO falling on breathers

13 September 2001 table of contents