Synergistic induction of severe hypothermia (poikilothermia) by limbic seizures, acepromazine and physical restraint: Role of noradrenergic α-1 receptors

• Published in: Pharmacology, biochemistry and behavior biochemistry and behavior, 2001-10, Vol.70 (2), p.341-352
• Main Authors: Persinger, M.A, O'Connor, R.P, Bureau, Y.R.J, Parker, G.H, Peredery, O, Zegil, M
• Format: Article
• Language: English
• Subjects: Acepromazine; Acepromazine - pharmacology; Adrenergic alpha-1 Receptor Antagonists; Adrenergic antagonists; Animals; Antimanic Agents; Biological and medical sciences; Body Temperature - drug effects; Body Temperature - physiology; Brain - drug effects; Brain - pathology; Brain - physiology; Brain damage; Core temperature; Dopamine antagonists; Dopamine Antagonists - pharmacology; Dose-Response Relationship, Drug; Drug Synergism; Food deprivation; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Hypothermia - chemically induced; Hypothermia - etiology; Hypothermia - physiopathology; Limbic seizures; Limbic System - drug effects; Limbic System - pathology; Limbic System - physiology; Lithium Chloride; Male; Medical sciences; Muscarinic Agonists; Nervous system (semeiology, syndromes); Neurology; phentomaline; Pilocarpine; prazosin; Rats; Rats, Wistar; Receptors, Adrenergic, alpha-1 - physiology; Restraint, Physical; Seizures - chemically induced
• ISSN: 0091-3057; 1873-5177
• DOI: 10.1016/S0091-3057(01)00619-0

The maintained production of extreme reductions in core temperature (20–22 °C) or poikilothermia can be reliably produced by the synergistic interaction of limbic seizures (induced by lithium and pilocarpine), postseizure administration of a single injection of acepromazine, and physical restraint. Administration of the specific and nonspecific dopamine antagonists haloperidol, chlorpromazine, SCH23390, or clozapine did not simulate the effect at clinically effective dosages. Single injections of phentolamine and prazosin but not of propranolol instead of acepromazine following the seizures produced the poikilothermia. This effect was also reproduced by reducing the amount of the rats' adipose weight before the induction of the seizures and physical restraint. Rats that had been restrained or not restrained and displayed either euthermia or hypothermia exhibited significantly different patterns in brain damage within limbic and thalamic structures.