Behavioral characterization of CD26 deficient mice in animal tests of anxiety and antidepressant-like activity

• Published in: Behavioural brain research 2006-08, Vol.171 (2), p.279-285
• Main Authors: El Yacoubi, Malika, Vaugeois, Jean-Marie, Marguet, Didier, Sauze, Nicole, Guieu, Régis, Costentin, Jean, Fenouillet, Emmanuel
• Format: Article
• Language: English
• Subjects: Affectivity. Emotion; Analysis of Variance; Animals; Anxiety; Anxiety - enzymology; Behavior, Animal - physiology; Biological and medical sciences; Depression - enzymology; Dipeptidyl Peptidase 4 - genetics; Dipeptidyl Peptidase 4 - metabolism; Dipeptidyl Peptidase 4 - physiology; DPPIV/CD26; Exploratory Behavior - physiology; Forced swim test; Fundamental and applied biological sciences. Psychology; Gene targeted inactivation; Immobility Response, Tonic - physiology; Life Sciences; Medical sciences; Mice; Mice, Inbred C57BL; Mice, Knockout; Motor activity; Motor Activity - physiology; Neurons and Cognition; Neuropharmacology; Personality. Affectivity; Pharmacology. Drug treatments; Psychoanaleptics: cns stimulant, antidepressant agent, nootropic agent, mood stabilizer..., (alzheimer disease); Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Psychopharmacology; Tail suspension test
• ISSN: 0166-4328; 1872-7549
• DOI: 10.1016/j.bbr.2006.04.003

CD26 exhibits a dipeptidylpeptidase-IV function (DPPIV) which regulates neuropeptide activity by N-terminal processing. Because abnormal plasma DPPIV was associated in mammals with behavioral changes, we examined the behavior of CD26−/− mice resulting from targeted inactivation of the gene. These animals had a decreased immobility in the forced swim and tail suspension tests, indicating a reduced depression-like behavior. We addressed some factors that could affect these results. No major differences between mutants and controls were observed in the black/white box test that investigates anxiety. In the hole-board apparatus that explores both curiosity and anxiety, CD26−/− mice of both genders made significantly more head dips than controls. In a motor activity test, mutants displayed higher horizontal and vertical activities i.e. increased novelty-induced behavioral activation. We conclude that DPPIV inactivation in mice broadly leads to an antidepressant-like and hyperactive phenotype.