Comparison of cerebrospinal fluid monoamine metabolite levels in dominant-aggressive and non-aggressive dogs.
Aggression has been shown to be related to reduced serotonergic activity in humans and non-human primates, and in rodents. We now studied the relationship between cerebrospinal fluid (CSF) monoamine metabolites and canine aggression in 21 dominant-aggressive dogs (Canis familiaris) and 19 controls. The diagnosis of dominance-related aggression was based upon a history of biting family members in contexts associated with dominance challenges. Post-mortem CSF 5-HIAA, MHPG and HVA were measured by high-performance liquid chromatography using electrochemical detection. Concentrations of CSF 5-HIAA (P = 0.01) and HVA (P < 0.001) were lower in the aggressive group (median values: 5-HIAA 202.0 pmol/ml; HVA 318.0 pmol/ml) than in controls (5-HIAA 298.0 pmol/ml; HVA 552.0 pmol/ml). No differences were noted in CSF MHPG levels. Differences in 5-HIAA were maintained after controlling for breed and age of dogs, but HVA differences may have been breed-dependent. Lower levels of 5-HIAA (P = 0.02) and HVA (P = 0.04) were found in the subgroup of aggressive dogs with a history of biting without warning (5-HIAA 196.0 pmol/ml; HVA 302.0 pmol/ml) compared to dogs that warned (5-HIAA 244.0 pmol/ml; HVA 400.0 pmol/ml). This study suggests that reduced serotonergic function is associated with aggressive behavior and impaired impulse control in dogs, a finding that is consistent with observations in primates, and suggests that serotonin modulates aggressive behavior throughout mammals.
Reisner
I R
IR
Department of Physiology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Mann
J J
JJ
Stanley
M
M
Huang
Y Y
YY
Houpt
K A
KA
D000374:Aggression; D000818:Animals; D015306:Biogenic Monoamines / Q000134:cerebrospinal fluid*; D004285:Dogs; D006719:Homovanillic Acid / Q000134:cerebrospinal fluid*; D006897:Hydroxyindoleacetic Acid / Q000134:cerebrospinal fluid*
D015306:Biogenic Monoamines; D006897:Hydroxyindoleacetic Acid; D006719:Homovanillic Acid