Effects of hypophysectomy on compulsive checking and cortical dendrites in an animal model of obsessive-compulsive disorder.

Hormones may modulate the symptoms of obsessive-compulsive disorder (OCD), but the evidence is equivocal and not consistent across studies, with findings of hormone-associated increases and decreases of symptoms. To assess whether a strong endocrine influence on OCD exists, the effects of hypophysectomy were examined in an animal model of OCD. The model involves repeated injections of the dopamine D2/D3 receptor agonist, quinpirole, to induce locomotor sensitization and compulsive checking behavior.

Effect of nicotine on quinpirole-induced checking behavior in rats: implications for obsessive-compulsive disorder.

Background: Rats treated chronically in a large, open field with the dopamine D2/D3 receptor agonist quinpirole (QNP) develop compulsive checking behavior as defined by a set of behavioral criteria. This paradigm has been suggested as an animal model of obsessive-compulsive disorder (OCD). Because nicotine blocks various behaviors induced by ontogenetic QNP administration, we asked whether nicotine could attenuate QNP-induced compulsive checking.