Pharmacological evaluation of the adequacy of marble burying as an animal model of compulsion and/or anxiety.

Marble-burying behavior in rodents has been used commonly as an animal model of compulsive and/or anxiety behavior. The purpose of this study was to further assess the adequacy of marble burying as a preclinical animal model of compulsive behaviors using pharmacological tools. In particular, we were interested in whether dopamine D2/D3 agonists (e.g. pramipexole) known to produce compulsive behaviors in humans would increase marble burying. The effects of pramipexole on marble-burying behavior and locomotor activity were compared with those of the following: diazepam, a drug known to decrease marble burying; D-amphetamine, a stimulant that increases locomotor activity; and methyl β-carboline-3-carboxylate, a β-carboline previously shown to produce anxiogenic effects in rodents. All drugs produced dose-dependent decreases in marble burying, which were not always related to the locomotor effects of these drugs. The inability of pramipexole and methyl β-carboline-3-carboxylate to increase marble burying questions the validity of this assay as an adequate animal model of compulsive and/or anxiety behavior.