Complex maze performance in rats: Effects of noradrenergic depletion and cholinergic blockade.

Noradrenergic (NA) involvement in acquisition (AQ) and retention (RET) of a shock-motivated 14-unit T-maze after intraperitoneal (ip) administration of DSP4, a neurotoxin that depletes forebrain NA, was evaluated in 2 experiments using 3-month-old male F-344 rats. In Experiment 1, DSP4 rats did not differ from saline-treated (SAL) rats on any measure of maze performance during AQ (DSP4 2 weeks prior to testing) nor during a RET test 2–3 weeks later (DSP4 immediately after the last AQ trial or 1 week after AQ). In Experiment 2, DSP4 and scopolamine (SCOP), a cholinergic (ACh) antagonist, were administered in combination to test for an NA-ACh interaction. DSP4 again had no effect on AQ performance nor did DSP4 interact with either dose of SCOP to further impair performance. SCOP impaired all measures of maze performance except shock duration. These experiments suggest that central NA systems may not be involved directly or interactively with ACh systems required for efficient performance in this maze. (PsycINFO Database Record (c) 2010 APA, all rights reserved)