Multiple within-day conflict testing to define the time course of anxiolytic drug effects

• Published in: Pharmacology, biochemistry and behavior biochemistry and behavior, 1996-02, Vol.53 (2), p.369-377
• Main Authors: Commissaris, Randall L., Xie, Zhongcong, Ninichuk, Paul J., Markovska, Victoria L.
• Format: Article
• Language: English
• Subjects: Animals; Anti-Anxiety Agents - pharmacology; Anxiety; Anxiolytics; Biological and medical sciences; Conflict (Psychology); Conflict behavior; Dizocilpine Maleate - pharmacology; Drinking Behavior - drug effects; Excitatory Amino Acid Antagonists - pharmacology; Female; Hypnotics and Sedatives - pharmacology; Medical sciences; MK-801; Neuropharmacology; Pharmacology. Drug treatments; Phenobarbital; Phenobarbital - pharmacology; Psycholeptics: tranquillizer, neuroleptic; Psychology. Psychoanalysis. Psychiatry; Psychopharmacology; Rats; Rats, Sprague-Dawley; Repeated testing procedures; Time course; Time Factors
• ISSN: 0091-3057; 1873-5177
• DOI: 10.1016/0091-3057(95)02036-5

The present article describes a method for multiple within-day conflict testing to conduct drug treatment time course studies more efficiently. Groups of female Sprague-Dawley rats were trained for conflict testing in a standard one-session/day procedure [conditioned suppression of drinking (CSD)]. In this task, thirsty rats (24 h water-restricted) drink from a tube that is electrified only when a tone is on (approximately 20% of the 10-min session time). In Experiment 1 it was found that there was no significant variation in CSD conflict behavior when subjects were tested at 0600, 1200, or 1800 h using the traditional procedure of one test/day. In Experiment 2, subjects were assigned to treatment groups such that there were three 5-min test sessions per day and the test-retest interval was either 2, 4, or 6 h (centered around 1200 h). Test-retest intervals of 6 h (i.e., tests at 0600, 1200, and 1800 h) resulted in comparable levels of punished responding across the repeated within-day tests, whereas test-retest intervals of 2 h and, to a lesser extent 4 h, resulted in unequal within-day conflict behavior characterized by a greater number of shocks accepted and a greater volume of water consumed during the earliest test periods each day. In another group of rats, it was determined that conflict behavior sampled five times/day in 3-min sessions separated by a 3-h test-retest interval (i.e., tests at 0600, 0900, 1200, 1500, and 1800 h) also resulted in stable conflict behavior across the various within-day test periods. In Experiment 3, it was found that acute IP challenges with anticonflict treatments that exhibit either a long duration of action (phenobarbital: 40 mg/kg) or a significant delay to onset in addition to a long duration (MK-801: 0.20 mg/kg) yielded time course data comparable to those obtained using the traditional one test/day procedure. These findings indicate that the use of multiple within-day conflict testing can greatly increase the efficiency of these procedures, particularly when drug treatment timecourse information is desired.