Effects of Psychological Stress on Autonomic Control of Heart in Rats

Abstract

Abstract:The aim of this study was to examine the effects of psychological stress on autonomic control of the heart in rats. For this purpose, we evoked anxiety-like or fear-like states in rats by means of classical conditioning and examined changes in autonomic nervous activity using an implanted telemetry system and power spectral analysis of heart rate variability. Anxiety-like states resulted in a significant increase in heart rate (HR), low frequency (LF) power, and LF/HF ratio, with no change in high frequency (HF) power. Fear-like states resulted in a significant increase in HR and a significant decrease in HF power with no significant change in both LF power and LF/HF ratio, although LF/HF ratio increased slightly. These results suggest that autonomic balance becomes predominant in sympathetic nervous activity in both anxiety-like and fear-like states. These changes in rats correspond to changes which are relevant to cardiovascular diseases in humans under many kinds of psychological stress. Therefore, the experimental design of this study is a useful experimental model for investigating the effects of psychological stress on autonomic control of the heart in humans.

Changes in Autonomic Control of Heart Associated with Classical Appetitive Conditioning in Rats

“…We previously investigated two kinds of emotional states associated with classical aversive conditioning in rats using an implanted telemetry system and power spectral analysis of HRV. The results demonstrated that the examination of changes in autonomic nervous activity is one useful method for classifying two different kinds of emotional states: "the stress-expecting state" and "the stress-received state" [11]. Moreover, in that study, the changes in autonomic nervous activity of the heart were clearly different from the results of the present study [11].…”

“…The results demonstrated that the examination of changes in autonomic nervous activity is one useful method for classifying two different kinds of emotional states: "the stress-expecting state" and "the stress-received state" [11]. Moreover, in that study, the changes in autonomic nervous activity of the heart were clearly different from the results of the present study [11]. Accordingly, we suggest that the changes in autonomic nervous activity of the heart might be a useful physiological index of motivational states or of receiving reward in rats, and this index might be applicable to diverse fields of research, for example, establishment of "animal welfare" in rats as experimental animals.…”

Effects of chronic moderate alcohol consumption and novel environment on heart rate variability in primates (Macaca fascicularis)

“…Although decreases in power across the spectrum occurred, they were most evident in the HF band, suggesting decreases in parasympathetic modulation of cardiac function (Pagani et al 1986). In rats, stressful conditions also have been shown to increase HR and LF power and increase the LF/HF ratio (Inagaki et al 2004).…”

Recent Advances in Telemetry Monitoring and Analysis for Laboratory Animals

“…These results suggest that autonomic balance becomes predominant in sympathetic nervous activity in both anxiety-like and fear-like states. These changes in rats correspond to changes which are relevant to cardiovascular diseases under many kinds of psychological stress (Inagaki, et al, 2004).…”