Nine weeks after the experiment began, the researchers observed that, as expected, the rats in the SHRSP control had higher blood pressure when compared to the normal control rats. Interestingly, in the group that fasted every other day, the SHRSP rats had significantly reduced blood pressure when compared with the
“Next, we investigated whether the microbiota was involved in the reduction of blood pressure we observed in the SHRSP rats that had fasted,” Durgan said.
The researchers transplanted the microbiota of the rats that had either fasted or fed without restrictions into germ-free rats, which have no microbiota of their own.
Durgan and his colleagues were excited to see that the germ-free rats that received the microbiota of normally fed SHRSP rats had higher blood pressure than the germ-free rats receiving microbiota from normal control rats, just like their corresponding microbiota donors.
“It was particularly interesting to see that the germ-free rats that received microbiota from the fasting SHRSP rats had significantly lowered the blood pressure than the rats that had received microbiota from SHRSP control rats,” Durgan said. “These results demonstrated that the alterations to the microbiota induced by fasting were sufficient to mediate the blood pressure-lowering effect of intermitting fasting.”