Biomaterial Database

Cardiac sympathetic overactivity and decreased baroreflex sensitivity in L-NAME hypertensive rats. 2001

H C Souza, and G Ballejo, and M C Salgado, and V J Da Silva, and H C Salgado

Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, 14049-900 Ribeirão Preto, São Paulo, Brazil.

The present study evaluated the possible changes in the autonomic control of heart rate in the hypertensive model induced by the inhibition of nitric oxide synthase. Rats were treated with N(G)-nitro-L-arginine methyl ester (L-NAME group) in the drinking water during 7 days, whereas control groups were treated with tap water (control group) or with the N(G)-nitro-D-arginine methyl ester (D-NAME group), an inactive isomer of the L-NAME molecule. The L-NAME group developed hypertension and tachycardia. The sequential blockade of the autonomic influences with propranolol and methylatropine indicated that the intrinsic heart rate did not differ among groups and revealed a sympathetic overactivity in the control of heart rate in the L-NAME group. The spectral density power of heart rate, calculated using fast-Fourier transformation, indicated a reduced variability in the low-frequency band (0.20-0.60 Hz) for the L-NAME group. The baroreflex sensitivity was also attenuated in these animals when compared with the normotensive control or D-NAME group. Overall, these data indicate cardiac sympathetic overactivity associated with a decreased baroreflex sensitivity in L-NAME hypertensive rats.

UI	MeSH Term	Description	Entries
D006973	Hypertension	Persistently high systemic arterial BLOOD PRESSURE. Based on multiple readings (BLOOD PRESSURE DETERMINATION), hypertension is currently defined as when SYSTOLIC PRESSURE is consistently greater than 140 mm Hg or when DIASTOLIC PRESSURE is consistently 90 mm Hg or more.	Blood Pressure, High,Blood Pressures, High,High Blood Pressure,High Blood Pressures
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
D010276	Parasympatholytics	Agents that inhibit the actions of the parasympathetic nervous system. The major group of drugs used therapeutically for this purpose is the MUSCARINIC ANTAGONISTS.	Antispasmodic,Antispasmodic Agent,Antispasmodic Drug,Antispasmodics,Parasympathetic-Blocking Agent,Parasympathetic-Blocking Agents,Parasympatholytic,Parasympatholytic Agent,Parasympatholytic Drug,Spasmolytic,Spasmolytics,Antispasmodic Agents,Antispasmodic Drugs,Antispasmodic Effect,Antispasmodic Effects,Parasympatholytic Agents,Parasympatholytic Drugs,Parasympatholytic Effect,Parasympatholytic Effects,Agent, Antispasmodic,Agent, Parasympathetic-Blocking,Agent, Parasympatholytic,Agents, Antispasmodic,Agents, Parasympathetic-Blocking,Agents, Parasympatholytic,Drug, Antispasmodic,Drug, Parasympatholytic,Drugs, Antispasmodic,Drugs, Parasympatholytic,Effect, Antispasmodic,Effect, Parasympatholytic,Effects, Antispasmodic,Effects, Parasympatholytic,Parasympathetic Blocking Agent,Parasympathetic Blocking Agents
D011433	Propranolol	A widely used non-cardioselective beta-adrenergic antagonist. Propranolol has been used for MYOCARDIAL INFARCTION; ARRHYTHMIA; ANGINA PECTORIS; HYPERTENSION; HYPERTHYROIDISM; MIGRAINE; PHEOCHROMOCYTOMA; and ANXIETY but adverse effects instigate replacement by newer drugs.	Dexpropranolol,AY-20694,Anaprilin,Anapriline,Avlocardyl,Betadren,Dociton,Inderal,Obsidan,Obzidan,Propanolol,Propranolol Hydrochloride,Rexigen,AY 20694,AY20694,Hydrochloride, Propranolol
D004791	Enzyme Inhibitors	Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.	Enzyme Inhibitor,Inhibitor, Enzyme,Inhibitors, Enzyme
D005583	Fourier Analysis	Analysis based on the mathematical function first formulated by Jean-Baptiste-Joseph Fourier in 1807. The function, known as the Fourier transform, describes the sinusoidal pattern of any fluctuating pattern in the physical world in terms of its amplitude and its phase. It has broad applications in biomedicine, e.g., analysis of the x-ray crystallography data pivotal in identifying the double helical nature of DNA and in analysis of other molecules, including viruses, and the modified back-projection algorithm universally used in computerized tomography imaging, etc. (From Segen, The Dictionary of Modern Medicine, 1992)	Fourier Series,Fourier Transform,Analysis, Cyclic,Analysis, Fourier,Cyclic Analysis,Analyses, Cyclic,Cyclic Analyses,Series, Fourier,Transform, Fourier
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
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