Medicine and Health Sciences Commons^™

Role Of Gamma-Aminobutyric Acid Type A (Gabaa) Receptor Subtypes In Acute Benzodiazepine Physical Dependence-Like Effects: Evidence From Squirrel Monkeys Responding Under A Schedule Of Food Presentation., Bradford D Fischer, Laura P Teixeira, Michael L Van Linn, Ojas A Namjoshi, James M Cook, James K Rowlett

Cooper Medical School of Rowan University Faculty Scholarship

RATIONALE: Assays of schedule-controlled responding can be used to characterize the pharmacology of benzodiazepines and other GABAA receptor modulators, and are sensitive to changes in drug effects that are related to physical dependence.

OBJECTIVE: The present study used this approach to investigate the role of GABAA receptor subtypes in mediating dependence-like effects following benzodiazepine administration.

METHODS: Squirrel monkeys (n = 6) were trained on a fixed-ratio schedule of food reinforcement. Initially, the response rate-decreasing effects of chlordiazepoxide (0.1-10 mg/kg; nonselective GABAA receptor agonist), zolpidem (0.032-1.0 mg/kg; α1 subunit-containing GABAA subtype-preferring agonist), and HZ-166 (0.1-10 mg/kg; functionally selective α2 and α3 …

Reinforcing Effects Of Compounds Lacking Intrinsic Efficacy At Α1 Subunit-Containing Gabaa Receptor Subtypes In Midazolam- But Not Cocaine-Experienced Rhesus Monkeys., Nina M Shinday, Eileen K Sawyer, Bradford D Fischer, Donna M Platt, Stephanie C Licata, John R Atack, Gerard R Dawson, David S Reynolds, James K Rowlett

Cooper Medical School of Rowan University Faculty Scholarship

Benzodiazepines are prescribed widely but their utility is limited by unwanted side effects, including abuse potential. The mechanisms underlying the abuse-related effects of benzodiazepines are not well understood, although α1 subunit-containing GABAA receptors have been proposed to have a critical role. Here, we examine the reinforcing effects of several compounds that vary with respect to intrinsic efficacy at α2, α3, and α5 subunit-containing GABAA receptors but lack efficacy at α1 subunit-containing GABAA receptors ('α1-sparing compounds'): MRK-623 (functional selectivity for α2/α3 subunit-containing receptors), TPA023B (functional selectivity for α2/α3/α5 subunit-containing receptors), and TP003 (functional selectivity for α3 subunit-containing receptors). The reinforcing effects …