Generating TrkA-KFG Mutant Mice for Behavioral Studies

The generation of TrkA-KFG mutant mice has been described elsewhere [20 (link)]. All tests were conducted on at least 3-month-old, age-matched, male mutants, or C57BL/6CR mice. Male mice were used to exclude the effects of sexual dimorphism and estrous phase on behavior. Animals were kept in the NCI vivarium in colony cages at an ambient temperature of 25 ± 2 °C and 45–55% relative humidity with 12 h light: dark cycle. The mice had free access to standard rodent pellet diet and drinking water. Donepezil (3 mg/kg i.p) was obtained from Sigma-Aldrich (USA). Picrotoxin (0.5 mg/kg i.p) and midazolam (1.25 mg/g i.p) were from Cayman Chemicals (USA). The drug dosage was based on results of pilot experiments and earlier publications [21 (link)–23 (link)]. TMT (2, 3, 5-Trimethyl-3-thiazoline) was obtained from PheroTech, Canada. All procedures were approved by NCI-Frederick ACUC committee and followed the National Institutes of Health Guidelines for animal care and use.