Dopamine D2L receptor- and age-related reduction in offensive aggression

The dopamine D2 receptor (D2) has been implicated in attention-deficit hype ractive disorder (ADHD) and aging. Two isoforms of D2 have been identified, termed D2L (long form) and D2S (short form). In this study, we investigate d the role of D2L in offensive aggression, using mice lacking the dopamine D2L receptor (D2L-/-) as a model system and the resident-intruder test. We found that D2L-/- mice showed much lower levels of aggression than wild-typ e mice. Interestingly, offensive aggression also decreased as the age of th e mice increased. These results suggest that both the D2L receptor and agin g play roles in the modulation of offensive aggression. This finding may co ntribute to our understanding of the neurobiological basis of aggression. N euroReport 12:1035-1038 (C) 2001 Lippincott Williams & Wilkins.