World Library  
Flag as Inappropriate
Email this Article

Penbutolol

Article Id: WHEBN0004036673
Reproduction Date:

Title: Penbutolol  
Author: World Heritage Encyclopedia
Language: English
Subject: List of MeSH codes (D02), Beta blockers, Atenolol/chlorthalidone, Alprenolol, Tertatolol
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Penbutolol

Penbutolol
Systematic (IUPAC) name
(S)-1-(tert-butylamino)-3-(2-cyclopentylphenoxy)propan-2-ol
Clinical data
Trade names Levatol
AHFS/Drugs.com
MedlinePlus
Identifiers
CAS Registry Number  YesY
ATC code C07
PubChem CID:
IUPHAR/BPS
DrugBank  N
ChemSpider  YesY
UNII  N
KEGG  YesY
ChEMBL  YesY
Chemical data
Formula C18H29NO2
Molecular mass
Documentation

 N   

Penbutolol (Levatol, Levatolol, Lobeta, Paginol, Hostabloc, Betapressin) is a medication in the class of beta blockers, used in the treatment of high blood pressure. Penbutolol is able to bind to both beta-1 adrenergic receptors and beta-2 adrenergic receptors (the two subtypes), thus making it a non-selective β blocker [1]. Penbutolol is a sympathomimetic drug with properties allowing it to act as a partial agonist at β adrenergic receptors [2]. Penbutolol has also been found to be one of very few compounds that are 5-HT1A antagonists. 5-HT1A receptors are activated by serotonin, which have many different actions in different species. This makes it difficult to create generalizations about serotonin and its effects [1].

Contents

  • Hypertension 1
  • β1 Blockade 2
  • Characteristics 3
  • References 4

Hypertension

Hypertension can result from a multitude of alterations to blood volume, heart or kidney function. Hypertension involving a high heart rate can lead to myocardial ischemia [3]. Penbutolol acts by blocking β adrenergic receptors and blocking the sympathetic nervous system to decrease the heart rate and cardiac output to lower arterial blood pressure. β blockers also decrease renin levels, which ultimately results in less water being reabsorbed by the kidneys and therefore a lower blood volume and blood pressure [3].

β1 Blockade

Penbutolol acts on the β1 adrenergic receptors in both the heart and the kidney. When β1 receptors are activated by a catecholamine, they stimulate a coupled G protein which activates adenylyl to convert adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP) [1]. The increase in cAMP leads to activation of protein kinase A (PKA), which alters the movement of calcium ions in heart muscle and increases heart rate [4]. Penbutolol blocks this and decreases heart rate, which lowers blood pressure. The ability of penbutolol to act as a partial agonist proves useful in the prevention of bradycardia as a result of decreasing the heart rate excessively [2]. Penbutolol binding β1 adrenergic receptors also alters kidney functions. Under normal physiological conditions, the enzyme renin converts angiotensinogen to angiotensin I, which will then be converted to angiotensin II. Angiotensin II stimulates the release of aldosterone from the adrenal gland, causing a decrease in electrolyte and water retention, ultimately increasing water excretion and decreasing blood volume and pressure [5].

Characteristics

Penbutolol is typically administered orally in doses of 20 mg per day [7]. It is rapidly absorbed from the gastrointestinal tract, has a bioavailability over 90% [6], and has a rapid onset of effect. Penbutolol has a half life of five hours [1], and a low frequency of side effects [7]. These side effects include dizziness, light headedness, and nausea [6]. When penbutolol is being metabolized, it undergoes a series of biotransformations, the main one being hydroxylation. One potential drawback of penbutolol is the inactivation of β2 adrenergic receptor, which makes this a less than ideal hypertensive treatment for people suffering from asthma or insulin dependent diabetes mellitus.

References

  1. Katzung, Bertram G. (1998). Basic and Clinical Pharmacology (7th ed.). London: Appleton & Lange. ISBN 0838505651
  2. Frishman, W. H., Covey, S. (1990). Penbutolol and carteolol: two new beta-adrenergic blockers with partial agonism. Journal of Clinical Pharmacology, 30(5):412-21
  3. Berdeaux, A., Duhaze, P., Giudicelli, J. F. (1982). Pharmacological analysis of beta adrenoceptor blockade-induced coronary blood flow redistribution in dogs using l-penbutolol. The Journal of Pharmacology and Experimental Therapeutics, 221(3):740-747
  4. Dent, M. R., Singal, T., Tappia, P. S., Sethi, R., Dhall, N. S. (2008). Signal transduction in the cardiovascular system in health and disease. Advances in Biochemistry in Health and Disease, 3:27-49
  5. Howland, Richard D., Mycek, Mary J. (2006). Lippincott’s Illustrated Reviews: Pharmacology (3rd ed.). New York: Lippincott Williams & Wilkins. ISBN 0781741181
  6. Vallner, J. J., Jun H. W., Needham, T. E., Stewart, J. T., Brown, W., Frazer, H., Honigberg, I. L. (1977). Plasma level studies of penbutolol after oral dose in man. Journal of Clinical pharmacology, 17(4):231-23
  7. Schoenberger, J. A. (1989). Usefulness of penbutolol for systemic hypertension: Penbutolol


This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 


Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.