PMID: 7085431Apr 1, 1982Paper

Hemodynamic responses to methoxamine in exercise-conditioned and aorta-constricted rats

Journal of Applied Physiology: Respiratory, Environmental and Exercise Physiology
E M HasserJ L Haithcoat


Hemodynamic responses to methoxamine hydrochloride (Vasoxyl) were determined in rats conditioned by a moderate treadmill exercise program and in rats subjected to 5 wk of abdominal aortic constriction. Rats of comparable age served as controls. Initial hemodynamic values for control rats were as follows: left ventricular pressure, 124 +/- 4 Torr and cardiac index, 145 +/- 8 ml . min-1 . kg-1. Although minor variations were noted, initial hemodynamic values for exercise-conditioned rats were within the normal range, and no left ventricular hypertrophy was present. Aorta-constricted rats exhibited a 50% increase in left ventricular weight and significant differences in left ventricular pressure (173 +/- 9 Torr) and cardiac index (117 +/- 10 ml . min-1 . kg-1). Sequentially increasing doses of methoxamine were infused to elevate myocardial preload and afterload. When compared with control rats, exercise-conditioned animals were better able to maintain cardiac index at comparable increases in either mean arterial or left ventricular end-diastolic pressures. In contrast, aorta-constricted rats demonstrated profound reductions in hemodynamic functions in response to methoxamine infusion. Directionally divergent hemodynamic results oc...Continue Reading


May 18, 2001·American Journal of Physiology. Heart and Circulatory Physiology·P J FadelP B Raven

Related Concepts

Ascending Aorta Structure
Diastolic Blood Pressure
Cardiac Output
Closure by Clamp
Pulse Rate
Metoxamine Wellcome
August Rats
Ventricular Function

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Lipidomics & Rhinovirus Infection

Lipidomics can be used to examine the lipid species involved with pathogenic conditions, such as viral associated inflammation. Discovered the latest research on Lipidomics & Rhinovirus Infection.

Spatio-Temporal Regulation of DNA Repair

DNA repair is a complex process regulated by several different classes of enzymes, including ligases, endonucleases, and polymerases. This feed focuses on the spatial and temporal regulation that accompanies DNA damage signaling and repair enzymes and processes.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Torsion Dystonia

Torsion dystonia is a movement disorder characterized by loss of control of voluntary movements appearing as sustained muscle contractions and/or abnormal postures. Here is the latest research.

Archaeal RNA Polymerase

Archaeal RNA polymerases are most similar to eukaryotic RNA polymerase II but require the support of only two archaeal general transcription factors, TBP (TATA-box binding protein) and TFB (archaeal homologue of the eukaryotic general transcription factor TFIIB) to initiate basal transcription. Here is the latest research on archaeal RNA polymerases.

Alzheimer's Disease: MS4A

Variants within the membrane-spanning 4-domains subfamily A (MS4A) gene cluster have recently been implicated in Alzheimer's disease in genome-wide association studies. Here is the latest research on Alzheimer's disease and MS4A.

Central Pontine Myelinolysis

Central Pontine Myelinolysis is a neurologic disorder caused most frequently by rapid correction of hyponatremia and is characterized by demyelination that affects the central portion of the base of the pons. Here is the latest research on this disease.