History and Basics of Pharmacology

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Questions and Answers

What is the primary focus of pharmacology?

The creation of new drugs

The historical use of plants as medicine

The study of drug interaction with living systems (correct)

The administration techniques for pain relief

Which of the following historical figures is considered the 'Father of Medicine'?

Hippocrates (correct)

Galen

Avicenna

Celsus

What is considered a major limitation of early pharmacological practices?

Use of advanced imaging techniques

Use of synthetic drugs

Mechanisms of action were not understood (correct)

Over-reliance on animal testing

Which of the following is a source of drugs mentioned in the historical context?

Herbal plants Signup and view all the answers

What does the term 'pharmakon' translate to in English?

Drug Signup and view all the answers

Which drug is NOT mentioned as an example in pharmacology?

Ibuprofen Signup and view all the answers

What was the purpose of using the recipe from Celsus during surgeries?

To sedate the patient for surgery Signup and view all the answers

In pharmacology, what is meant by 'mechanism of action'?

The physiological effects caused by a drug Signup and view all the answers

Which natural product is derived from the plant Atropa belladonna?

Atropine Signup and view all the answers

What is Exenatide extracted from?

Saliva of Gila monster Signup and view all the answers

Which biological target is NOT considered a main target for drug action?

Hormones Signup and view all the answers

Human growth factor is isolated from which part of the body?

Pituitary gland Signup and view all the answers

Hirudin is extracted from which of the following?

Leeches Signup and view all the answers

What is the mechanism of action primarily involved with most drugs?

Biological interactions with cellular macromolecules Signup and view all the answers

Which drug is derived from the fungus Penicillium notatum?

Penicillin Signup and view all the answers

What is a key factor affecting the clinical efficacy of drugs?

Dose of the drug Signup and view all the answers

What is the primary action of local anesthetics like sodium channel blockers?

They block Na+ channels. Signup and view all the answers

How does Captopril contribute to lowering blood pressure?

By inhibiting the ACE enzyme. Signup and view all the answers

Which mechanism describes how receptor agonists function?

They fully activate the receptor. Signup and view all the answers

What role do carrier molecules play in cellular function?

They transport various biological compounds. Signup and view all the answers

Which of the following best defines a receptor in pharmacology?

A target for drug binding that mediates actions. Signup and view all the answers

What is the effect of digoxin when it binds to sodium/potassium-ATPase pump?

Increases cardiac output. Signup and view all the answers

Which type of receptor is primarily involved in direct ion channel activation?

Ligand-gated ion channels. Signup and view all the answers

What distinguishes partial agonists from full agonists?

They activate receptors with less efficacy. Signup and view all the answers

What is the effector domain for the insulin receptor?

Enzymes (Tyrosine Kinase) Signup and view all the answers

Which receptor is associated with G-protein effector domains?

a-adrenergic Receptor Signup and view all the answers

Which of these drugs was the first antibiotic introduced?

Penicillin Signup and view all the answers

What does teratogenicity refer to?

Drug-induced fetal malformations Signup and view all the answers

Which of the following receptors is a nuclear receptor?

Vitamin D Receptor Signup and view all the answers

Which of the following milestones in drug therapy occurred first?

Discovered active principles by Van Hohenheim Signup and view all the answers

Thalidomide was initially used as what type of medication?

Hypnotic & anti-morning sickness Signup and view all the answers

Which organization is not associated with drug regulation in the UK?

CAPA Signup and view all the answers

Study Notes

History of Pharmacology

Hippocrates, known as the "Father of Medicine", created the first collection of medical texts, "The Hippocratic Collection", and promoted the importance of observation and examination in medicine.
The text highlights early practices using willow bark to relieve pain, reflecting an understanding of herbal remedies.
Amputations in ancient times were often painful, leading to the use of Henbane or mandrake root for anesthesia.
Celsus used boiled poppy heads with raisin wine to create a form of anesthesia for amputations.

Pharmacology Defined

Pharmacology is the study of how drugs interact with living organisms, leading to functional modifications within these systems.
Drugs do not create new conditions but rather modify existing ones.
Pharmacology examines how drugs work at the cellular level, including their effects on individual proteins, cells, tissues, and organs.

Sources of Drugs

Plants and natural products:
- Atropine (from Atropa belladonna)
- Digoxin (from Digitalis purpurea)
- Opiates (from Papaver somniferum)
- Quinine (from Cinchona bark)
- Cannabis (from Cannabis sativa)
- Cocaine (from Erythroxylum coca)
Microorganisms:
- Penicillin (from Penicillium notatum)
- Neomycin (from Streptomyces fradiae)
- Vancomycin (from Amycolatopsis orientalis)
- Botulinum toxin (from Clostridium botulinum)
- Cephalosporins (from Cephalosporium acremonium)
Animals:
- Insulin (from porcine or bovine pancreas)
- Exenatide (from Gila monster saliva)
- Allantoin (from maggots)
- Human growth factor (from the pituitary gland)
- Hirudin (from leeches)
- Teprotide (from snake venom)

Key Factors in Pharmacology

Mechanism of action: Explains how a drug exerts its effect.
Dose: Refers to the amount of drug needed to achieve the desired effect, including ineffective, clinically effective, and toxic levels.
Selectivity: Indicates a drug's ability to target specific biological pathways.
Side effects: Undesired consequences of drug use.
Risk/benefit ratio: A balance between potential benefits and potential harm of a drug.

Mechanisms of Drug Action

Physical mechanisms: Less common, examples include osmosis or adsorption, like osmotic laxatives.
Chemical mechanisms: Neutralization reactions are an example, such as antacids.
Biological/Cellular protein targets:
Ion channels (e.g., sodium channels blocked by local anesthetics)
Enzymes (e.g., captopril inhibits ACE enzyme, sildenafil inhibits phosphodiesterase)
Carrier molecules (e.g., sodium-potassium pump)
Receptors (e.g., insulin receptors, adrenergic receptors, glucocorticoid receptors)

Receptor Types

Receptors are specialized macromolecules that bind drugs and mediate their effects.
Key-lock model: A drug's affinity for a receptor determines its ability to bind, while intrinsic activity determines the ability to initiate a response.
Types of drug actions on receptors:
Agonists: Fully activate receptors.
Partial agonists: Partially activate receptors.
Antagonists: Block receptors

Receptor Classification

Ligand-gated ion channels: The receptor's effector domain is an ion channel (e.g., nicotinic receptors).
Enzyme-linked receptors: The receptor's effector domain is an enzyme (e.g., insulin receptors with tyrosine kinase activity).
G-protein-coupled receptors: The receptor's effector domain is a G-protein (e.g., adrenergic receptors).
Nuclear receptors: The receptor's effector domain is located in the nucleus, influencing DNA (e.g., glucocorticoid receptors).

Drug Safety

Teratogenicity: The ability of a drug to cause fetal abnormalities.
- Examples include Thalidomide (limb malformations) and Rubella (fetal abnormalities).
Drug regulatory bodies: Ensure drug safety (e.g., CAPA in Egypt, EDA in Egypt, MHRA in the UK, CSM in the UK).

Milestones in Drug Therapy

1600 BC: Egyptian medical papyrus - early record of medicine.
200 AD: Galen's theory of disease (blood, phlegm, yellow bile, black bile).
1516: Van Hohenheim questioned Galen's theory and focused on active principles in natural products.
1804: Sertürner isolated morphine, the first pure drug.
1909: Ehrlich synthesized arsenical compounds used in syphilis treatment.
1935: Domagk developed sulphonamides, the first selective antimicrobials.
1945: Fleming, Chain, and Florey discovered penicillin, the first antibiotic.
1960s: Black's study on drug function led to the development of beta-blockers (propranolol) and H2 antagonists (cimetidine).
2000s: Biologics like antibodies emerged for treating diseases like rheumatoid arthritis (e.g., etanercept, infliximab).

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Description

Explore the fascinating history of pharmacology, from Hippocrates' foundational texts to the early use of herbal remedies and anesthesia. This quiz covers key developments in how drugs interact with living organisms and their origins. Test your knowledge about the essential principles and historical milestones in the field of pharmacology.