Effects of certain cerebral circulation activating drugs on regional cerebral blood flow in rats.

The effects of certain cerebral circulation activating drugs on regional cerebral blood flow (rCBF) in the frontal cortex (FCOR), hippocampus (HPC) and nucleus caudatus (CAD) were investigated using the hydrogen clearance method in rats. All the drugs used in the present study, i.e., ozagrel, ifenprodil, pentoxifylline, cinnarizine and dilazep, caused an increase in rCBF in the FCOR, HPC and CAD. Ozagrel was the most potent in increasing rCBF at the FCOR. Ozagrel, ifenprodil, cinnarizine and dilazep were more effective than pentoxifylline in increasing rCBF at the HPC. On the other hand, all the drugs showed almost the same potency in increasing rCBF at the CAD. These results suggested that measurement of rCBF is useful for estimating the efficacy of cerebral circulation activating drugs.