Arecoline, but not haloperidol, induces changes in the permeability of the blood-brain barrier in the rat.
The aim of the present study was to investigate the existence of alterations of the blood-brain barrier (BBB) permeability in rats injected with centrally acting drugs, by calculating a unidirectional blood-to-brain transfer constant (Ki) for the circulating tracer [14C]-alpha-aminoisobutyric acid. The intraperitoneal (i.p.) injection of the dopaminergic antagonist haloperidol (1 mg kg-1) did not modify the regional BBB permeability. When the cholinomimetic agent arecoline hydrobromide (6.25 mg kg-1) was injected i.p. into methylatropine-pretreated rats, it induced a significant decrease of Ki values within the frontal cortex, parietal cortex, striatum and brain-stem. Our findings emphasize two concepts: (1) centrally acting drugs, such as arecoline, can induce changes in the BBB permeability, through several mechanisms; (2) there is no predictable correlation of drug stimulation of specific brain neuronal pathways and changes in the permeability of the BBB.
Saija
A
A
Department Farmaco-Biologico, School of Pharmacy, University of Messina, Italy.
Princi
P
P
De Pasquale
R
R
Costa
G
G
D000621:Aminoisobutyric Acids / Q000494:pharmacology; D000818:Animals; D001115:Arecoline / Q000494:pharmacology*; D001285:Atropine / Q000494:pharmacology; D001810:Blood Volume / Q000187:drug effects; D001812:Blood-Brain Barrier / Q000187:drug effects*; D006220:Haloperidol / Q000494:pharmacology*; D007700:Kinetics; D008297:Male; D010539:Permeability; D051381:Rats; D011919:Rats, Inbred Strains; D012039:Regional Blood Flow / Q000187:drug effects
D000621:Aminoisobutyric Acids; C100049:2-aminoisobutyric acid; D001115:Arecoline; D001285:Atropine; D006220:Haloperidol