Basic Pharmacology (Viva Preparation)

Q: 1. What is the difference between receptor and neurotransmitter?

Ans. Receptor is a structural protein molecule on the cell surface or within the cytoplasm that binds to a specific factor, such as a hormone, antigen, or neurotransmitter. Whereas neurotransmitters are the chemicals that carry messages between different nerve cells or between nerve cell and muscles.

Q: 2. What are adrenergic receptors?

Ans. These are reactive components of effector tissues. These receptors are activated by norepinephrine and/or epinephrine and by various adrenergic drugs. On activation, it results in a change of effector tissue function e.g. relaxation of bronchial muscles and contraction of arteriolar muscles.

Q: 3. What do you know about G proteins?

Ans. These are intracellular membrane associated proteins stimulated by various receptors such as beta adrenergic receptors. They work as second messengers. Due to high affinity for guanine nucleotides, they are termed as G proteins.

Q: 4. Name some of the cholinergic antagonists.

Ans. Atropine, Botulinum toxin, Scopolamine, Tubocurarine, Erythroidin (nicotinic cholinergic antagonist)

Q: 5. Name some of the transmitter substances.

Ans. Acetylcholine, Norepinephrine, Dopamine, Serotonin, Gamma aminobutyric acid (GABA), Glutamate

Q: 6. What are the main types of receptors?

Ans. Four main types of receptors: 1) Ligand gated channels 2) G protein coupled receptors 3) Nuclear receptors 4) Kinase linked receptors

Q:7. What are ligand gated channels?

Ans. These are made up of subunits of protein that form a central core.

Q: 8. What are the main types of ligand gated channels?

Ans. 1) Nicotinic receptor 2) GABA receptor

Q: 9. What do you know about G protein coupled receptors?

Ans. They form a family of receptors with seven membrane spanning helices. They are associated with physiological responses by second messengers.

Q:10. What do you know about nuclear receptors?

Ans. They are used to regulate transcription and protein synthesis. These receptors for steroid hormones and thyroid hormones are located in the cell nucleus.

Q:11. What are kinase linked receptors?

Ans. These are surface receptors that have intrinsic tyrosine kinase activity. They include receptors for cytokines, insulin and growth factors.

Q: 12. What do you mean by second messenger?

Ans. An intermediate molecule produced as a result of hormone receptor interaction e.g. adenosine 3c,5c-cyclic monophosphate, Calcium and Inositide.

Q: 13. What do you know about baroreceptor?

Ans. Nerve endings those are sensitive to blood pressure changes.

Q: 14. What is pharmacology?

Ans. It is the science of drugs including their origin or sources, chemistry, production, composition, pharmacokinetics, therapeutic use, and toxicology.

Q: 15. What is the difference between pharmacy and pharmacology?

Ans. The art or science, practice or profession of preparing, preserving, compounding, and dispensing drugs used as medical treatments is pharmacy whereas pharmacology talks with special reference to the mechanism of action of the drug on a (particular) disease.

JNJ 7777120

Its full name is 1-[(5-chloro-1H-indol-2-yl)carbonyl]-4-methylpiperazine . (Thurmond et al.) It is developed by Johnson and Johnson Pharmaceutical R & D as an anti-inflammatory agent. It is better in the treatment of itching. (wikipedia.com, 2009)

It blocks the chemotaxis induced by histamine in mouse. (Thurmond et al.)

References:
1. JNJ 7777120 (2009). wikipedia, retrieved on 03. 03. 2009 from http://en.wikipedia.org/wiki/JNJ_7777120

2. Thurmond, R. L., Desai, P. J., Dunford, P. J., Leung, W. P. F., Hofstra, C. L., Jiang, W., Nguyen, S., Riley, J. P., Sun, S., Williams, K. N., Edwards, J. P., and Karlsson, L., (2004). Journal of Pharmacology And Experimental Therapeutics, 404-413.

SRT 1720

Action:
It is an activator of small molecule SIRT 1 (which is an NAD + dependent deacetylase and has the ability of removing acetyl groups from a variey of compounds). It has similar activity as that of resveratrol but is 1000 times more active than resveratrol. (wikipedia, 2009)

Uses:
It is under investigation for the treatment of obesity and diabetes.(wikipedia, 2009)

References:
Wikipedia, (2009). SRT 1720. Retreived on 27, February 2009 from http://en.wikipedia.org/wiki/SRT1720

Resveratrol

Its other name is 3,5,4′-trihydrostilbene. (1) Resveratrol is one the naturally occuring phytoalexin compound. This is found in grapes.

Actions:
Resveratrol has been found to increase the life span of yeast and worms. It is thought that it stimulates a deacetylase enzyme namely SIRT1. This enzyme have the ability of regulatin several transcriptional factors and enzymes which are responsible for the nutritional availability. (Mitchell D Knutson et al.)

Therapeutic uses:
It has found practical uses as an anti-cancer agent for breast cancer in both hormone dependent and hormone independent. (Hiroyuki Nakagawa et al.)
It has also been found that it has the ability of protecting against inflammatory arthritis. (N. Elmali et al.)

References:
(1) Encyclopedia of Genetics, Genomics, Proteomics and Informatics, 2008, page 1684

Hiroyuki Nakagawa, Yasuhiko Kiyozuka, Yoshiko Uemura, Hideto Senzaki, Nobuaki Shikata, Koshiro Hioki and Airo Tsubura, 2001, Resveratrol inhibits human breast cancer cell growth and may mitigate the effect of linoleic acid, a potent breast cancer cell stimulator, Journal of Cancer Research and Clinical Oncology, Volume 127, 258-264

Mitchell D Knutson, Christiaan Leeuwenburgh, 2008, Resveratrol and novel potent activators of SIRT1: effects on aging and age-related diseases, Nutrition reviews, volume 66, 591-596

N. Elmali , O. Baysal , A. Harma , I. Esenkaya and B. Mizrak, 2006, Effects of Resveratrol in Inflammatory Arthritis , Inflammation, volume 30, 1-6

Further reading:
A Cardiologist's Guide to Anti-Aging, Antioxidants & Resveratrol by M.D. Dr. William S. Gruss

Resveratrol in Health and Disease (Oxidative Stress and Disease) by Bharat B. Aggarwal and Shishir Shishodia

Resveratrol and Human Health by Debasis Bagchi

Effects of Naturally Occurring Compounds on HumanCancer Cells: Anticancer Activity of Resveratrol, Piceatannol,Gallic Acid & their Analogs by Philipp Saiko

Natural products:
Source Naturals Resveratrol, Tablets, 60 tablets (Read Nutrition facts)

Copyright (c), 2009, http://jeepakistan.blogspot.com

Tigliane

Structure of Tigliane:General Characteristics:
It has almost same system as that of daphnanes i.e. tricyclo tetradecane ring system. It has additional gem-dimethyl cyclopropane appended to the 6-membered ring. (Its most) famous (part) is Phorbol, which was named in about 25 BC by King Juba II of Mauritania. Wender, on one hand, and Cha, on the other hand, has completed its synthesis.

Action:
It primarily acts on protein kinase C (PKC, which is important for regulating cellular growth and differentiation).

Isolation of tiglianes:
It has been isolated from Euphorbia and Thymelaceae as esters.

Therapeutic uses:
It was primarily used for tumors, parasites, migraines, venereal diseases and as purgatives.
It has been found that C12 deoxy derivative blocks formation of the tumor.

Adverse effects:
Its most important tumor promoting example is Tetradodecanoyl phorbol acetate.

Further reading:
Naturally Occurring Phorbol Esters by Evans

Terbutaline

It is a member of the family of medications which is in use for
1. stopping the contractions of preterm labor (tocolytics)
2. asthma

It is a beta 2 adrenergic receptor agonist.

Pharmacokinetics:
The inhaled form of terbutaline starts working in 10-15 minutes and lasts for about 5-6 hours.

Side effects:
It may cause tachycardia, pulmonary edema, hypokalemia and in fetus it may also cause hypoglycemia.

Further reading:
Beta 2-agonists in Asthma Treatment (Lung Biology in Health and Disease) by Romain Pauwels and Paul O. Byrne

Fragmentation

In cell biology, fragmentation is the breaking apart of cells or cell organelles into smaller parts. Fragmentation may serve as a normal function for the cell, but may also be the result of a disorder.

Functions of cell fragmentation include:
Reproduction
Apoptosis

Disorders:
Microangiopathic diseases results in red blood cell fragmentation into schistocytes.

Further reading:
Biology: A Self-Teaching Guide, 2nd edition by Steven Daniel Garber