Peculiarities of autonomic regulation assessed by variability of hemodynamic parameters in rats with different stress resistance

Abstract

Analysis of contribution of sympathetic and parasympathetic systems into heart rate variability carried out using atenolol and atropine showed that August rats are characterized by enhanced tone of the sympathetic system and reduced tone of the parasympathetic system compared to Wistar rats. Reduced tone of the parasympathetic system is also confirmed by lower sensitivity of the baroreflex. Blockade of NO synthesis with Nw-nitro-L-arginine more markedly increased blood pressure variability in August rats compared to Wistar rats. The data attest to a certain rigidity of the autonomic cardiovascular regulation in August rats.

Influence of Central Neurotransmitters on Heart Rate Variability in Outbred Rats at Rest and during Acute Stress: Nature of Very-Low-Wave Spectrum Component Revisited

“…Respiratory arrhythmia, also known as high-frequency (HF) component of parasympathetic nature, is considered to be the basic component of heart rate variability spectrum (HRV) [2,3,5,11]. It is assumed that slow LF-waves are associated with vascular tone regulation, and both sympathetic and parasympathetic neural inputs associated with barorefl ex control of heart rate participate in their formation [4,5,12]. The nature of VLF-component of the heart rate wave structure is still least studied [2,11].…”

Age- and Sex-Related Changes in Heart Rate Variability Under Conditions of Blockade or Stimulation of Peripheral Adrenoceptor in Outbred Rats

“…Methods of heart rate variability (HRV) analysis combined with blockade or stimulation of receptors to neuroautonomic transmitters, are often used in the studies of cardiac function regulation mechanisms [3,4]. In order to identify the specifi c role of adrenergic and cholinergic mechanisms in the formation of HRV waves, pharmacological tests are conducted [4,8].…”

“…In order to identify the specifi c role of adrenergic and cholinergic mechanisms in the formation of HRV waves, pharmacological tests are conducted [4,8]. To resolve the controversial issues in this fi eld, it seems important to analyze changes in HRV parameters in the experimental animals taking into consideration the age-and sex-related specifi c features of maturation and functioning of the autonomous nervous system.…”

Cluster Analysis of Extracardiac Control of the Heart Rate in Random-Bred Albino Rats at Rest

“…The method of variation pulsometry is employed to examine the age-related peculiarities of vagosympathetic control of rat heart, as well as the effects of desympathization [4,5], stress [2], and other factors on the cardiac function. Power spectrum analysis of HRV revealed specificity of autonomic control in Wistar and August rats [6] and clarified the physiological nature of the wave structure of the heart rate [11,12]. However, most experimental papers use routine approach to analyze the group-average HRV indices, which neglects the initial state of the control systems in the individual animals.…”