Catecholamines, Biology

Assignment Help:

Catecholamines increase activation of Ca2+ via beta-adrenergic receptors and the adenyl cyclase system.

Dopamine has both alpha and beta and dopaminergic effects.  Its beta effects in the heart occur largely through the release of endogenous norepinephrine, which may be largely depleted in a failing heart. As such, the benefits of dopamine administration, if any, occur at low doses (e.g., 0.02 mg/kg per minute), where it may induce renal arterial vasodilatation. In general, it is employed in association with more potent inotropic agents (e.g., dobutamine).

Dobutamine characterized by an increase in cardiac output and a decrease in ventricular filling pressure with little change in heart rate. There is modest rise in arterial pressure and decrease in peripheral vascular resistance. The positive inotropic activity of dobutamine is mediated by direct stimulation of beta-adrenergic receptors in the myocardium.

Dobutamine infusion generally is begun at 2 µg/kg per minute and titrated to optimize cardiac output while reducing LV filling pressure. The major side effects of dobutamine are an excessive increase in heart rate with high doses and ventricular arrhythmias.


Related Discussions:- Catecholamines

Components of treatment of nkhdc, The components of treatment of NKHDC are:...

The components of treatment of NKHDC are: 1) control of water loss. 2) control of sugar using insulin. 3) adjust electrolytes like sodium and potassium. 4) control infe

Karyokinesis, At the beginning of the process in an animal cell, the partit...

At the beginning of the process in an animal cell, the partition of the centriole takes place, which has been duplicated during Interphase but were in the same centrosome. Bipol

Tail - structure of the sperm, Tail - Structure of the Sperm The tail ...

Tail - Structure of the Sperm The tail or flagellum is the longest part of the sperm. By its movement it causes the sperm to swim with the head forward. It consists of a thin

Describe the nature of the polymorphism, 1. DNA damage can occur spontaneou...

1. DNA damage can occur spontaneously or be induced by external factors. Describe the types of DNA damage caused by external factors and how they are repaired in prokaryotes and eu

What are similarities between peroxisomes and lysosomes, Q. What are the mo...

Q. What are the morphological, chemical and functional similarities and differences between peroxisomes and lysosomes? Similarities: Peroxisomes and lysosomes are small membran

Ecology and ecosystem, Ecology and Ecosystem The concepts of environme...

Ecology and Ecosystem The concepts of environment, ecology, ecosystem, energy flow and nutrient cycling in the foundation course on Science and Technology. As you are aware ec

What is the heterotrophic hypothesis on the origin of life, What is the het...

What is the heterotrophic hypothesis on the origin of life? As per to the heterotrophic hypothesis the first living beings were very simple heterotrophic organisms that is not

List a few important uses of food hydrocolloids, List a few important uses ...

List a few important uses of food hydrocolloids. A few important uses of food hydrocolloids are: to increase viscosity and to stabilize food products. Its other uses  include u

Condition type of change to be transmitted to the offspring, What are the s...

What are the situations in which the environment can alter the genotype of an individual? What is the condition for this type of change to be transmitted to the offspring? The

Animals vs plants, Animals vs Plants Organisms are of two main types an...

Animals vs Plants Organisms are of two main types animals and plants, although all the above mentioned Unifying concepts of Biology apply equally to both animals and plants, ye

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd