The researchers did this research with the purpose of exploring the beneficial effects of repeated episodes of whole body hypoxic preconditioning (WHPC) on preeclampsia (PE)-like symptoms in rats.

The researchers performed WHPC by exposing rats to low O2 and normal O2 of 10 min each in four alternate cycles.

L-NAME induced preeclampsia (PE) like symptoms in rats along with a decrease in the cystathionine-β-synthase (CBS) activity in the placental tissue, plasma levels of H2S, and NO metabolites in pregnant rats. Two (GD9, GD14) and three episodes (GD9, GD14, and GD18) of WHPC improved PE-like symptoms with an increase in CBS activity and H2S levels. cystathionine-β-synthase (CBS) inhibitor, amino-oxyacetic acid abolished the beneficial effects of three episodes of WHPC, while H2S donor, 4-methylbenzenecarbothioamide, 4-MBC attenuated PE-like symptoms.

The study concluded that the whole body hypoxic preconditioning (WHPC) attenuates L-NAME-induced PE-like symptoms due to an increase in cystathionine-β-synthase (CBS) activity and H2S-production. Other researchers need to do further research to explore beneficial effects and possible mechanisms of repeated episodes of whole-body hypoxic preconditioning in a rat model of preeclampsia.