Understanding Drug Receptors and Actions
Receptors: Drug Interaction Sites
Receptors are macromolecules, present either on the cell surface, cytoplasm, or in the nucleus, where drugs bind and interact to produce cellular changes. Receptors are mostly proteins.
Classification of Receptors
Receptors are classified into the following types:
- G-Protein Coupled Receptors
- Ion Channel Receptors
- JAK-STAT Binding Receptors
- Enzymatic Receptors
- Nuclear Receptors
G-Protein Coupled Receptors (GPCRs)
GPCRs are a large family of cell membrane receptors crucial
Read MoreDrug Properties & Metabolism: Impact on Biological Action
Physicochemical Properties & Biological Action
Physicochemical properties refer to the physical and chemical characteristics of a drug molecule that influence its behavior in biological systems. These properties play a crucial role in determining the drug’s absorption, distribution, metabolism, and excretion (ADME).
Key Physicochemical Properties
These properties include:
- Ionization
- Solubility
- Partition Coefficient
- Hydrogen Bonding
- Protein Binding
- Chelation
- Bioisosterism
- Geometrical Isomerism
- Optical Isomerism
Ionization
Ionization
Read MorePharmaceutical Agents: Mechanisms, Development, and Resistance
Anticancer Drugs: Mechanisms and Resistance
Anticancer drugs, also known as chemotherapy agents, are pharmacological substances designed to treat malignant diseases by inhibiting the growth and proliferation of cancer cells. These drugs operate through various mechanisms, targeting specific cellular processes essential for cancer cell survival and replication. The primary goals of anticancer therapies include damaging the DNA of cancer cells, inhibiting the synthesis of new DNA strands, and disrupting
Read MoreUnderstanding Food Browning: Maillard Reaction and Enzymatic Processes
Food Browning: Types and Mechanisms
Overview of Food Changes
Food undergoes various changes that can affect its quality, safety, and appearance. These changes can be broadly categorized as physical, chemical, or biotic.
Physical Factors
- UV Light
- Oxygen
- Temperature
- pH
Chemical Factors
- Oxidation of lipids
- Browning reactions
- Toxic pollutants
- Natural additives
Biotic Factors
- Microbiological activity
- Parasitological contamination
The Maillard Reaction: Non-Enzymatic Browning
Definition and Characteristics
The Maillard
Read MoreOrganic Chemistry: Carboxylic Acids, Amines, and Heterocycles
Unit 1: Carboxylic Acids and Their Derivatives
Preparation of Carboxylic Acids
Oxidation Reactions
- Primary alcohols → Carboxylic acids (using KMnO4, CrO3, etc.)
- Aldehydes → Carboxylic acids
- Ketones (via haloform reaction in methyl ketones)
Ester Hydrolysis
- Acidic hydrolysis: RCOOR’ + H2O → RCOOH + R’OH
- Alkaline hydrolysis (saponification): RCOOR’ + OH− → RCOO− + R’OH
Important Reactions of Carboxylic Acids
Hell-Volhard-Zelinsky Reaction
- α-halogenation of carboxylic acids using Br2 + PBr3
- Mechanism:
Cellular Transport and Plasma Membrane Structures
Macrotransport: Cellular Uptake and Release
Characteristics of Macrotransport
- Transport of large molecules/particles into and out of the cell
- Involving deformation/folding of the plasma membrane
Types of Macrotransport
- Endocytosis: Transport into the cell
- Pinocytosis (“cell drinking”)
- Phagocytosis (“cell eating”)
- Exocytosis: Transport out of the cell
Endocytosis
Phagocytosis vs. Pinocytosis: Key Differences
- Size of the material engulfed:
- Phagocytosis: > 250 nm vacuoles
- Pinocytosis: < 150 nm vesicles
- Size