title: Interactions between N-methyl-D-aspartate and nitric oxide in the modulation of ultrasonic vocalizations of infant rats.
abstract: The effects of interactions between N-methyl-D-aspartate (NMDA) and nitric oxide on ultrasonic vocalizations, motor activity and body temperature was investigated in 9-10-day-old rat pups. The competitive NMDA receptor antagonist, 3-((+/-)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP), and the nitric oxide synthase inhibitor, nitro-L-arginine-methyl ester (L-NAME), decreased the emission of ultrasonic vocalizations while NMDA and the nitric oxide precursor, L-arginine, produced a trend toward increased emission of ultrasonic vocalizations. CCP also attenuated the geotaxic response. Co-administration of CPP with L-NAME virtually abolished the emission of ultrasonic vocalizations and the ability to show the geotaxic response while co-administration of NMDA with L-arginine increased the emission of ultrasonic vocalizations and decreased body temperature with no effect on the geotaxic response. NMDA and L-arginine reversed the effects of L-NAME, but not of CPP, on ultrasonic vocalizations. L-arginine but not NMDA antagonized the effect of CPP on the geotaxic response. Our results confirmed the functional coupling between NMDA receptor activation and nitric oxide in modulating anxiety-like behavior and motor coordination in infant rats.
authors.affiliation: Department of Psychology, Dalhousie University, B3K 4J1, Halifax, Nova Scotia, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Podhorna
authors.forename: R E
authors.initials: RE
authors.lastname: Brown
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001120:Arginine / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects; D001831:Body Temperature / Q000187:drug effects; D004347:Drug Interactions; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005260:Female; D018466:Gravity Sensing / Q000187:drug effects; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D016202:N-Methylaspartate / Q000494:pharmacology*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology; D051381:Rats; D020318:Rats, Long-Evans; D014465:Ultrasonics; D014828:Vocalization, Animal / Q000187:drug effects*
chemical_list: D018691:Excitatory Amino Acid Antagonists; D010879:Piperazines; D009569:Nitric Oxide; D016202:N-Methylaspartate; D001120:Arginine; C050592:3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid; D019331:NG-Nitroarginine Methyl Ester