Premium
Inhibition of ultrasonic vocalizations by beta‐adrenoceptor agonists
Author(s) -
Blumberg Mark S.,
Johnson Eric D.,
MiddlemisBrown Jessica E.
Publication year - 2005
Publication title -
developmental psychobiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.055
H-Index - 93
eISSN - 1098-2302
pISSN - 0012-1630
DOI - 10.1002/dev.20070
Subject(s) - beta (programming language) , adrenergic receptor , ultrasonic sensor , endocrinology , medicine , chemistry , biology , receptor , computer science , programming language , radiology
Infant rat ultrasonic vocalizations (USVs) are widely believed to result from the induction of an emotional state of anxiety or distress. This perspective, however, is not easily reconciled with the demonstration by W. J. Farrell and J. R. Alberts 2000 that norepinephrine, a nonselective beta‐adrenoceptor agonist with anxiogenic properties, inhibits production of USVs. Here, Farrell and Alberts' finding was replicated and extended with 12‐day‐old rats using a conventional isolation paradigm. First, treatment with norepinephrine (1 mg/kg) significantly inhibited ultrasound production while also increasing body temperature. Next, treatment with the beta‐2 agonist terbutaline (1 mg/kg) and the beta‐3 agonist CL‐316243 (1 mg/kg), but not the beta‐1 agonist dobutamine (1 mg/kg), inhibited ultrasound production; only CL‐316243 increased body temperature. The unexpected inhibition of USVs by terbutaline, a potent bronchodilator, was replicated using a slightly modified procedure; again, body temperature was unaffected by terbutaline administration. In no experiment was inhibition of USVs related to changes in motor activity. Altogether, these results suggest either that ultrasound production is not a valid indicator of anxiety or that anxiety in infant rats is produced by neuropharmacological mechanisms that differ fundamentally from those in adults. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 47: 66–76, 2005.