Transient intrauterine hypotension causes apoptosis in fetal rat brain and affects learning.

Hypotensive episodes are frequent during pregnancy, and their functional effect on fetal brain has not been studied. We produced systemic hypotension for 30 min during mid-gestation in pregnant rats and examined their offspring on postnatal days 1 and 28. When compared with sham controls, the brain of the hypotensive group contained more TUNEL-positive cells in the hippocampal and periventricular regions on both time points. Spatial learning assessed by water milk maze test was impaired in 28-day-old pups of the hypotensive mothers. According to these results, transient maternal hypotension can induce apoptotic cell death in fetal brain and affect learning. Similar mechanisms may be considered and investigated in the pathogenesis of human learning disorders.