The long-term bio-behavioural effects of juvenile sildenafil treatment in Sprague-Dawley versus flinders sensitive line rats

Abstract

Abstract Objective: To investigate the long-term effects of juvenile sub-chronic sildenafil (SIL) treatment on the depressive-like behaviour and hippocampal brain-derived neurotrophic factor (BDNF) levels of adult Sprague-Dawley (SD) versus Flinders Sensitive Line (FSL) rats. Methods: SD and FSL rats were divided into pre-pubertal and pubertal groups, whereafter 14-day saline or SIL treatment was initiated. Pre-pubertal and pubertal rats were treated from postnatal day 21 (PND21) and PND35, respectively. The open field and forced swim tests (FST) were performed on PND60, followed by hippocampal BDNF level analysis 1 day later. Results: FSL rats displayed greater immobility in the FST compared to SD rats (p < 0.0001), which was reduced by SIL (p < 0.0001), regardless of treatment period. Hippocampal BDNF levels were unaltered by SIL in all treatment groups (p > 0.05). Conclusion: Juvenile sub-chronic SIL treatment reduces the risk of depressive-like behaviour manifesting during young adulthood in genetically susceptible rats.