Nicotine-induced enhancements in the five-choice serial reaction time task in rats are strain-dependent

Rationale: Clinically, nicotine improves attention, but this has proven difficult to demonstrate preclinically. We tested nicotine in Sprague-Dawley (SD) and Lister hooded (LH) rats in the five-choice serial reaction time task. Since SD rats demonstrate lower asymptotic performance than LH rats, we surmised that nicotine would only improve performance in this strain. Methods: Rats were placed in operant chambers 10 min after nicotine treatment (0.001-0.2 mg/kg). Results: Nicotine dose-dependently increased correct responses only in SD rats (similar to 20% at the highest dose). By contrast, nicotine dose-dependently increased omission errors and reduced trials completed in both strains of rat, and dose-dependently reduced tray responses in SD rats. Conclusion: The magnitude of improvement in accuracy seen with nicotine in SD rats is greater than previously demonstrated using lesion or parametric manipulation models in other strains of rat in this test of attention. Although this suggests that the SD strain may be a useful tool for future studies, other task parameters, such as stimulus duration, may have to be optimum to demonstrate the magnitude of improvement observed presently.