Changes in proton T1 in dog brains due to the administration of haloperidol

Changes in proton T1 in dog brains due to the administration of haloperidol were determined by the intravenous administration of a single dose of 20 mg of haloperidol to mongrel dogs. The MRI used was the Aberdeen type with the static magnetic field of 0.1 T. A coil made exclusively for these animals (bore diameter 120 mm) was used. There was a significant increase in the T1 value in the striate body 30 minutes and more (within two hours) after the administration of haloperidol. Subtraction images were also obtained by subtracting the image of the pre-treatment (control) T1 values from the image of the post-treatment values (2 hours after the injection). The subtraction images also revealed increases in the T1 values of the striate body.