ABSTRACT
The aim of the present work was to identify the role of ATP acting on specific P2X receptors in the central mechanisms of thermoregulation. Immunohistochemical studies demonstrated that brainstem structures involved in controlling body temperature contained large number of nerve cells bearing P2X ATP receptors. Experiments on conscious rats involving intracerebroventricular administration of an ATP analog and P2X antagonists showed that both activation and blockade of central P2X receptors produced marked changes in body temperature. Analysis of the effects of these substances provided grounds for suggesting that ATP acting on P2X receptors fulfils an important function in the mechanisms of transmitting afferent information from peripheral thermal receptors to thermoregulatory centers in the brainstem with responsibility for heat loss, while in pyrogen-induced fever ATP acting on these receptors may be involved in the activity of the endogenous antipyretic system.
Subject(s)
Adenosine Triphosphate/physiology , Body Temperature Regulation/physiology , Receptors, Purinergic P2/physiology , Adaptation, Physiological , Adenosine Triphosphate/analogs & derivatives , Adenosine Triphosphate/pharmacology , Animals , Body Temperature Regulation/drug effects , Endotoxins/pharmacology , Fever/physiopathology , Hypothalamus/cytology , Immunohistochemistry , Male , Medulla Oblongata/cytology , Medulla Oblongata/physiology , Neurons, Afferent/physiology , Purinergic P2 Receptor Agonists , Purinergic P2 Receptor Antagonists , Rats , Rats, Sprague-Dawley , Rats, Wistar , TemperatureABSTRACT
The aim of the present study was to elucidate the role of extracellular ATP acting on specific P2X receptors in the central mechanisms of thermoregulation. Using immunohistochemistry methods, it was found that the brainstem structures involved in the body temperature regulation contain a large number of nerve cells which possess P2X receptors for ATP. Experiments with intracerebroventricular application of a stable ATP analogue and P2X receptor antagonists to conscious rats showed that both activation and blockade of central P2X receptors resulted in marked changes in body temperature. Analysis of the effects of these agents suggests that ATP by acting on P2X receptors performs an important function in the mechanisms of transmission of afferent information coming from peripheral thermoreceptors to the brainstem thermoregulatory centres responsible for heat loss, and during pyrogen-induced fever can be involved in the action of the endogenous antipyretic system.
