The average difference in CBF between cells exposed to 100 nM P
and control cells based on sixteen fallopian tube samples from eight mice (paired comparisons). The CBF for each cell was first normalized against its baseline CBF. Progesterone was added after 30 minutes. For each individual mouse the difference between cells exposed to P4 and control cells was calculated for every time point. The mean differences over the first 30 minutes (baseline period) and the last 30 minutes are shown as crosshatched lines.