Biomaterial Database

Modulation of chronotropic and inotropic heart vagus actions as a non-pressor effect of angiotensin II in the anaesthetized rat. 1998

C Wicher, and G A Biewald, and M Hüller

Institute of Physiology II (Heart-Circulation Physiology), Medical Faculty, Friedrich Schiller University Jena, Germany.

(1) In vagotomized, anaesthetized rats, effects of stimulation of cardiac N. vagus (2-25 Hz) on cardiac and circulatory functions were studied: we recorded transient reductions in heart rate (HR), in left-ventricular systolic pressure (LV Ps), in maximal change in left-ventricular pressure development (dp/dt)max and in mean arterial pressure (MAP, A. femoralis). (2) Bolus injection of angiotensin II (AII, 2.5-100 microg/kg body weight) caused (a) transient increases in HR, LV Ps and MAP (pressor effects, maximal changes occurred within 3 min after injection), and (b) dose-dependently reduced effects of vagus stimulation (non-pressor effects, recorded 10 min after injection). Due to fast breakdown of All in the circulatory system, all observed vagus stimulation effects were completely recovered within 1 h after injection. (3) Plasma concentration of AII was recorded with a highly specific radioimmunoassay: 10 min after AII injection (non-pressor range), plasma concentration was clearly higher than physiological levels in all experiments with 10 microg AII/kg at least. (4) Treatment with propranolol (beta-adrenoceptor blocker, 1 mg/kg body weight) did not reduce the vagus effects alone, but decreased the modulatory AII effects. This result hints at the activation of sympathetic beta-adrenergic receptors by AII counteracting the parasympathetic cardiac control.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009206	Myocardium	The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.	Muscle, Cardiac,Muscle, Heart,Cardiac Muscle,Myocardia,Cardiac Muscles,Heart Muscle,Heart Muscles,Muscles, Cardiac,Muscles, Heart
D003864	Depression, Chemical	The decrease in a measurable parameter of a PHYSIOLOGICAL PROCESS, including cellular, microbial, and plant; immunological, cardiovascular, respiratory, reproductive, urinary, digestive, neural, musculoskeletal, ocular, and skin physiological processes; or METABOLIC PROCESS, including enzymatic and other pharmacological processes, by a drug or other chemical.	Chemical Depression,Chemical Depressions,Depressions, Chemical
D006321	Heart	The hollow, muscular organ that maintains the circulation of the blood.	Hearts
D006339	Heart Rate	The number of times the HEART VENTRICLES contract per unit of time, usually per minute.	Cardiac Rate,Chronotropism, Cardiac,Heart Rate Control,Heartbeat,Pulse Rate,Cardiac Chronotropy,Cardiac Chronotropism,Cardiac Rates,Chronotropy, Cardiac,Control, Heart Rate,Heart Rates,Heartbeats,Pulse Rates,Rate Control, Heart,Rate, Cardiac,Rate, Heart,Rate, Pulse
D000758	Anesthesia	A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.
D000804	Angiotensin II	An octapeptide that is a potent but labile vasoconstrictor. It is produced from angiotensin I after the removal of two amino acids at the C-terminal by ANGIOTENSIN CONVERTING ENZYME. The amino acid in position 5 varies in different species. To block VASOCONSTRICTION and HYPERTENSION effect of angiotensin II, patients are often treated with ACE INHIBITORS or with ANGIOTENSIN II TYPE 1 RECEPTOR BLOCKERS.	Angiotensin II, Ile(5)-,Angiotensin II, Val(5)-,5-L-Isoleucine Angiotensin II,ANG-(1-8)Octapeptide,Angiotensin II, Isoleucine(5)-,Angiotensin II, Valine(5)-,Angiotensin-(1-8) Octapeptide,Isoleucine(5)-Angiotensin,Isoleucyl(5)-Angiotensin II,Valyl(5)-Angiotensin II,5 L Isoleucine Angiotensin II,Angiotensin II, 5-L-Isoleucine
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014630	Vagus Nerve	The 10th cranial nerve. The vagus is a mixed nerve which contains somatic afferents (from skin in back of the ear and the external auditory meatus), visceral afferents (from the pharynx, larynx, thorax, and abdomen), parasympathetic efferents (to the thorax and abdomen), and efferents to striated muscle (of the larynx and pharynx).	Cranial Nerve X,Pneumogastric Nerve,Tenth Cranial Nerve,Nerve X,Nervus Vagus,Cranial Nerve, Tenth,Cranial Nerves, Tenth,Nerve X, Cranial,Nerve Xs,Nerve, Pneumogastric,Nerve, Tenth Cranial,Nerve, Vagus,Nerves, Pneumogastric,Nerves, Tenth Cranial,Nerves, Vagus,Pneumogastric Nerves,Tenth Cranial Nerves,Vagus Nerves,Vagus, Nervus
D014662	Vasoconstrictor Agents	Drugs used to cause constriction of the blood vessels.	Vasoactive Agonist,Vasoactive Agonists,Vasoconstrictor,Vasoconstrictor Agent,Vasoconstrictor Drug,Vasopressor Agent,Vasopressor Agents,Vasoconstrictor Drugs,Vasoconstrictors,Agent, Vasoconstrictor,Agent, Vasopressor,Agents, Vasoconstrictor,Agents, Vasopressor,Agonist, Vasoactive,Agonists, Vasoactive,Drug, Vasoconstrictor,Drugs, Vasoconstrictor