The Relationship between Anxiety, Depression-Like Behavior, and Arterial Pressure: A Comparative Study in 13-Month-Old Wistar, WKY, and SHR Rats

It is known that hypertension may be associated with some mental disorders and cognitive impairment. The complex relationship between anxiety and hypertension results in significant inconsistency among clinical data. In this study, we investigate the relationships between hypertension, anxiety, and depression in 13-month-old male rats of three genetically related normotensive Wistar and WKY and hypertensive SHR strains. We estimate arterial pressure (AP) and behavioral indicators using the open field test (OFT), elevated plus maze (EPM), and sucrose preference test. Higher locomotor and exploratory activity and lower anxiety are observed in the SHR rats in comparison with the normotensive Wistar- and WKY-strain rats. Correlation analysis does not reveal any relations between the indicators of anxiety in the OFT and EPM and AP values either in outbred Wistar or SHR rats. In WKY rats, moderate correlations are found between the AP value and the number of grooming episodes and entries into the center arena in the OFT. Thus, no relationships are revealed between the AP values and the indicators of anxiety and depression-like behavior.