The mouse spleen white pulp response to continuous hypoxia. A digital image processing analysis.

Ninety days old male mice of the CFW strain, placed under standard conditions for studies of periodicity, showed a 24 hours variation pattern in the spleen white pulp surface, in cross sections. This pattern was modified by hypoxia during the first 18 hours of continuous treatment. Since this time onwards a new steady state was reached, although the spleen of hypoxic animals was always smaller than in the controls. As the modifications were measured in pixel counts -a magnitude which can be easily transformed into square micrometers- they can be attributed to a real size variation and not to an apparent growth and decay due to environmental vasoactive phenomena.