This site is an archive of a closed Robert Wood Johnson Foundation program, provided for educational and historical purposes. Please note that this content is not routinely updated and that contact information and social links may not work.
Effects of acute stress on cardiac endocannabinoids, lipogenesis, and inflammation in rats
Objective: Trauma exposure can precipitate acute/post-traumatic stress responses (AS/PTSD) and disabling cardiovascular disorders (CVD). Identifying acute stress-related physiologic changes that may increase CVD risk could inform development of early CVD-prevention strategies. The endocannabinoid system (ECS) regulates hypothalamic-pituitary-adrenal (HPA) axis response and stress-related cardiovascular function. We examine stress-related endocannabinoid system (ECS) activity and its association with cardiovascular biochemistry/function following acute stress.
Methods: Rodents (n=8-16/group) were exposed to predator odor or saline; elevated plus maze (EPM), blood pressure (BP), serum and cardiac tissue ECS markers, and lipid metabolism were assessed at 24h and 2wks post-exposure.
Results: At 24h the predator odor group demonstrated anxiety-like behavior and had (a) elevated serum markers of cardiac failure/damage (brain natriuretic peptide [BNP]: 275.1 vs. 234.6, p=0.007; troponin-I: 1.50 vs. 0.78, p=0.076), lipogenesis (triacylglycerols [TAG]: 123.5 vs. 85.93, p=0.018), and inflammation (stearoyl delta-9 desaturase activity [SCD-16]: 0.21 vs. 0.07, p<0.001); (b) significant decrease in cardiac endocannabinoid (2-arachidonoyl-sn-glycerol, 2-AG: 29.90 vs. 65.95, p<0.001) and fatty acid ethanolamides (FAE: oleoylethanolamide, OEA: 114.3 vs. 125.4, p=0.047; palmitoylethanolamide, PEA: 72.96 vs. 82.87, p=0.008); and (c) increased cardiac inflammation (IL-1β/IL-6 ratio: 19.79 vs.13.57, p=0.038; TNF-α/IL-6 ratio: 1.73 vs. 1.03, p=0.019) and oxidative stress (thiobarbituric acid reactive substances [TBARS]: 7.81 vs. 7.05, p=0.022), that were associated with cardiac steatosis (higher TAG: 1.09 vs. 0.72, p<0.001). Cardiac lipogenesis persisted, and elevated BP emerged two weeks after exposure.
Conclusions: Acute psychological stress elicits ECS-related cardiac responses associated with persistent, potentially-pathological changes in rat cardiovascular biochemistry/function.