The protective effects of intermittent hypoxia

Hi everyone,

Happy (almost) Fall!

A few weeks ago, we learned that intermittent hypoxia increases nitric oxide (NO) production and storage.

The paper I’m sharing this week examines NO’s protective effects during hypoxia.

The protective role of nitric oxide during adaptation to hypoxia

(Read on website)

The experiment gradually adapted mice to a simulated altitude of ~5000 m (>16K ft).

After the acclimation, the mice nearly doubled their NO metabolites. Their NO storage significantly increased as well.

Hypoxia protects against NO-overproduction

They also gave a subset of mice a condition causing excessive NO, which dropped their blood pressure about 36 mm Hg. However, when the mice were acclimated to hypoxia, they only showed a 19 mm Hg drop.

Hypoxia protects against NO-deficiency

Mice given a condition of NO-deficiency (which increases blood pressure) also saw protective effects from hypoxia. Without hypoxia, their blood pressure increased ~80 mm Hg. With adaptation, it only increased ~20 mm Hg.

Overall, these results indicate that adaptation to hypoxia protects against both over- and under-production of NO.

The final sentence from their abstract sums up the benefits nicely:

The data suggest that NO stores induced by adaptation to hypoxia can either bind excessive NO to protect the organism against NO overproduction or provide a NO reserve to be used in NO deficiency.

In good breath,
Nick