Effects of epinephrine on heart rate variability and cytokines in a rat sepsis model

Figures

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  FIGURE 1. Experimental protocol used in the study. Propranolol or esmolol were given 1 hour before lipopolysaccharide (LPS) inoculation, and epinephrine (EPI) infusion was begun 0.5 hour before LPS inoculation. Measurements were obtained until 4 hours after LPS inoculation.

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  FIGURE 2. Changes in HRV parameters in LPS-induced rat sepsis model, and in relation to EPI and propranolol/esmolol administration. A total of 36 male Sprague-Dawley rats were randomized into two control groups and four experimental groups of six animals each. Black dotted line denotes saline placebo group: LPS(-), EPI(-). Black solid line means EPI control group: LPS(-), EPI(+). Blue solid line represents Group A: LPS (+), EPI (-). Red solid line represents Group B: LPS(+), EPI(+), + propranolol. Green solid line represents Group C: LPS (+), EPI(+). Purple solid line represent Group D: LPS(+), EPI(+), + esmolol. We analyzed both time- and frequency-domain measures of HRV, as follows: (A) - heart rate; (B) – SDANN; (C) - SD delta; (D) - pNN50; (E) – VLF (very low frequency); (F) – LF (low frequency); (G) – HF (high frequency); and (H) - LF/HF. EPI: Epinephrine; HRV: Heart rate variability; LPS: Lipopolysaccharide; SDANN: Standard deviation of the average NN intervals; pNN50: Percentage of successive RR intervals that differ by more than 50ms.

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  FIGURE 3. Changes in the levels of pro-inflammatory cytokines in LPS-induced rat sepsis model, and in relation to EPI and propranolol/esmolol administration. A total of 36 male Sprague-Dawley rats were randomized into two control groups and four experimental groups of six animals each. Black dotted line denotes saline placebo group: LPS(-), EPI(-). Black solid line means EPI control group: LPS(-), EPI(+). Blue solid line represents Group A: LPS (+), EPI (-). Red solid line represents Group B: LPS(+), EPI(+), + propranolol. Green solid line represents Group C: LPS (+), EPI(+). Purple solid line represents Group D: LPS(+), EPI(+), + esmolol. (A) - IL-1β; (B) - IL-6; and (C) - TNF-α. EPI: Epinephrine; HRV: Heart rate variability; LPS: Lipopolysaccharide; IL-1β: Interleukin 1 beta; IL-6: Interleukin 6; TNF-α: Tumor necrosis factor alpha.

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  FIGURE 4. Changes in mean blood pressure in LPS-induced rat sepsis model, and in relation to EPI and propranolol/esmolol administration. A total of 36 male Sprague-Dawley rats were randomized into two control groups and four experimental groups of six animals each. Black dotted line denotes saline placebo group: LPS(-), EPI(-). Black solid line means EPI control group: LPS(-), EPI(+). Blue solid line represents Group A: LPS (+), EPI (-); Red solid line represents Group B: LPS(+), EPI(+), + propranolol. Green solid line represents Group C: LPS (+), EPI(+); Purple solid line represents Group D: LPS(+), EPI(+), + esmolol. EPI: Epinephrine; LPS: Lipopolysaccharide; MBP: Mean blood pressure.