SFRP5 prevents memory impairment induced by WNT5A in male Wistar rats

Wingless-type family members (Wnt5a) and secreted frizzled-related protein 5 (SFRP5) play important roles in the central nervous system during development. However, the effects of Wnt5a and SFRP5 on learning and memory in adults remain unknown. Here, we evaluated the effects of Wnt5a and SFRP5 on the consolidation of passive avoidance memory in rats. Forty-two male Wistar rats were divided into six groups including saline, Wnt5a(10ng/mL), SFRP5 (30, 60 and 120 ng/ml), and SFRP5+ Wnt5a groups (n=7). Animals were anaesthetized and cannulated for intra-cerebroventricular (ICV) injection using stereotaxic apparatus. Drugs were injected one hour after the training in step-through passive avoidance learning, and 24 h later, memory retention was evaluated. Data were analyzed by one-way ANOVA and post hoc Tucky tests. Findings showed that injection of Wnt5a in a dose of 10 ng/mL, one hour after training, significantly impaired consolidation of passive avoidance memory (P = 0.01), whereas ICV injection of SFRP5 (60 and 120 ng/ml) (P=0.02) showed a significant facilitatory effect on consolidation of memory compared to the saline receiving group. Also, pretreatment with 60 ng/ml SFRP5, 15 min before WNT5A prevents memory impairment. Our findings suggest that ICV injection of Wnt5a one hour after training impairs consolidation of passive avoidance memory, but pretreatment with SFRP5 significantly prevents the deleterious effect of Wnt5a. © 2022, The Author(s), under exclusive licence to Springer Nature Switzerland AG.