The effect of delta-9-tetrahydrocannabinol on rat cerebrospinal fluid
A. C. Mancall, G. J. DiGregorio, C. B. Brill and E. Ruch
The effect of delta-9-tetrahydrocannabinol (THC) on cerebrospinal fluid
(CSF) flow in rats was studied. The ventricular system of rats anesthetized
with ketamine sulfate was cannulated via cisternal puncture, and CSF
production was recorded. When administered in doses of 25 mg/kg to 45 mg/kg
intraperitoneally, THC caused inhibition of CSF flow; in larger doses a
smaller response was noted. In response to THC, CSF flow showed an initial
drop, a return toward baseline, and a secondary decrease. It is postulated
that this biphasic effect is due to a combination of THC's sympathomimetic
effects on the CNS plus the local action that this drug has on choroidal
synaptosomal neurotransmitters.
