Oxygen requirement for prostaglandin biosynthesis.

The formation of prostaglandins by vesicular gland cyclooxygenase can be regulated by O2 concentrations below 30 micron (20 mm Hg) with an apparent Km value of about 5 micron. This result suggests that most mammalian tissues might be expected normally to have sufficient O2 for some synthesis, and that only occasionally, would the level of oxygen available within some tissues become marginally inadequate to sustain a high rate of prostaglandin biosynthesis.