ABSTRACT
A comparative analysis is made of various methods for processing electrocardiograms and RR-interval sequences. This analysis was carried out by using standard nonlinear-dynamics algorithms and methods. Apart from that, we assessed the expediency of using a number of characteristics to classify the cardiovascular system's state under stress.
Subject(s)
Algorithms , Cardiovascular System/physiopathology , Electrocardiography/methods , Stress, Physiological/physiology , Animals , Cardiovascular Physiological Phenomena , Humans , Nonlinear DynamicsABSTRACT
A comparative analysis is made of various methods for processing electrocardiograms and RR-interval sequences. This analysis was carried out by using standard nonlinear-dynamics algorithms and methods. Apart from that, we assessed the expediency of using a number of characteristics to classify the cardiovascular system's state under stress.
Subject(s)
Cardiovascular System/physiopathology , Signal Processing, Computer-Assisted , Stress, Physiological/physiopathology , Algorithms , Electrocardiography , Fourier Analysis , Heart Rate/physiology , HumansABSTRACT
Dynamics of changes in adrenal and plasma corticosterone and the development of cerebrovascular lesions were studied in both male and female rats, exposed to strong stress (combined immobilization and intermittent found sound for 2 hours). Plasma corticosterone levels in stressed females were 460% and 660% of the control values when measured on stress minute 10 and 120. The corresponding values in male rats were 220% and 360%. The stress-induced dilatation of brain vessels and the increases in vascular permeability were less pronounced in females than in males, when studied 0.1 and 24 hours after termination of stress. The number of brain perivascular haemorrhages was markedly reduced in females compared with males. It is supposed that higher resistance to stress-induced cerebrovascular lesions in females may be attributed to higher functional reserves of steroidogenesis.
Subject(s)
Adrenal Cortex/physiopathology , Cerebral Hemorrhage/etiology , Stress, Psychological/complications , Acoustic Stimulation , Acute Disease , Animals , Brain/blood supply , Brain/physiopathology , Capillary Permeability , Cerebral Hemorrhage/physiopathology , Corticosterone/analysis , Disease Susceptibility/physiopathology , Female , Male , Rats , Restraint, Physical , Stress, Psychological/physiopathology , Time FactorsABSTRACT
Adrenal and plasma corticosterone levels under conditions of preoperative stress (removal from animal to experimental rooms, removal from a home cage, handling, weighing and injecting with saline) were more than 2-fold higher in female rats than in male ones. Females, compared with males, showed more pronounced decrease in corticosterone responses to preoperative stress and laparotomy under nembutal anesthesia, which blocked stress-induced emotional activation. One hour after recovery from anesthesia laparotomized females but not males, demonstrated a significant (5-fold) increase in plasma corticosterone level. The absolute values of plasma corticosterone in laparotomized females, compared with males, were 2-fold lower under anesthesia but 2-fold higher after recovery from anesthesia. It is supposed that in females, compared with males, stress-induced emotional tension plays more considerable role in endocrine stress responses. This provides higher adrenocortical sensitivity to stress in conscious female rats than in male animals.
