Neurohumoral Transmission, Co-transmission and Classification of Neurotransmitters

Neurohumoral TransmissionNeurohumoral transmission is when electrical signals are transmitted from one neuron to another via chemical messengers called neurotransmitters.

Neurohumoral transmission can occur either at the synapse, where two neurons meet or via gap junctions, which are specialized cell-cell junctions that allow electrical signals to pass directly from one cell to another.
When came o…

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Organization and Function of ANS

Autonomic Nervous SystemThe sympathetic nervous system also shuts down nonessential functions, such as digestion and reproduction, so that the body can focus on dealing with the stressor.

Example:
If you see a bear on the side of the road, your sympathetic nervous system will kick in and prepare you to either fight or run away.
Parasympathetic Nervous SystemThe parasympathetic nervous system is resp…

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Drug Discovery and Clinical Evaluation of New Drugs

What is Drug discovery?The process of discovering and developing new drugs is known as drug discovery. It involves a series of steps that begins with identifying potential drug targets and end with the approval of a new drug by the Food and Drug Administration (FDA).

This can be done through a variety of methods, including studying natural substances, synthesizing new compounds, or modifying exist…

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Drug Interactions (Pharmacokinetic and Pharmacodynamic)

Pharmacokinetic Drug InteractionsThe absorption, distribution, metabolism, and excretion of drugs can be affected by the presence of another drug. This is known as a pharmacokinetic drug interaction.

Some factors that can affect drug interactions include:
The route of administrationThe dose of each drugThe duration of each drug's effectThe time interval between taking each drugThe age, weight, …

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Adverse Drug Reactions

Adverse drug reactions (ADRs), also known as side effects, are a type of medical error that can occur when prescribing, dispensing, or administering medications. They can range in severity from mild to life-threatening and can be temporary or long-lasting.The most common ADRs are skin rashes, gastrointestinal upset, and dizziness. More serious ADRs can include heart attacks, strokes, and seizures…

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Dose Response Relationship, Therapeutic Index, Combined Effects of Drugs and Factors Modifying Drug Action

Dose-response RelationshipThe dosage-response link is the connection between a drug's dose and the response it generates.
This relationship can be linear or nonlinear.In general, the higher the dose of a drug, the greater the response.However, there can be diminishing returns at very high doses, where the increase in response is not proportional to the increase in dose.The dose-response relati…

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Transmembrane Enzyme Linked Receptors, Transmembrane JAK-STAT binding Receptor and Receptors that Regulate Transcription Factors

The fаte оf оur сells is mаinly deсided by the intrасellulаr signаling раthwаys thаt соntrоl meсhаnisms invоlved in рhenоtyрiсаl mоdifiсаtiоns. This сruсiаl rоle beсоmes even mоre signifiсаnt in саnсer сells thаt rely uроn а vаst, соmрliсаted, аnd inter-соnneсted netwоrk оf signаling раthwаys fоr their survivаl аnd рrоliferаtiоn. Signаling раthwаys аre mоstly асtivаted thrоugh сell membrаne reсe…

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Drug Receptors Interactions Signal Transduction Mechanisms, G-protein–coupled Receptors, Ion Channel Receptor

Drug Receptors Interactions Signal Transduction MechanismsHow does this mechanism work?Step 1: The drug attaches itself to the receptor.
Step 2: The drug's affinity for the receptor changes the conformation (shape) of the receptor.
Step 3: The change in the receptor's shape activates a signaling cascade within the cell.
Step 4: This signaling cascade leads to a cellular response, which may b…

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Essential Drugs Concept and Routes of Drug Administration

Essential Drugs ConceptAlthough there are many drugs on the market, the majority of them may not be essential for the majority of people. Based on this fact, the World Health Organization (WHO) created the concept of "essential medications" in 1977. Essential drugs, according to this definition, are those that meet the population's most pressing healthcare demands. They are chosen w…

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Receptor Theories and Classification of Receptors, Regulation of Receptors

Receptor TheoriesReceptors are distributed throughout the body and are responsible for detecting internal and external environment changes.
They pass on this information to the central nervous system to respond.
Two main theories explain how receptors work:
The lock-and-key theory: This theory states that receptors are specific to a particular molecule type and can only bind with that molecule.
How …

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Pharmacodynamics- Principles and Mechanisms of Drug Action

The word pharmacology originates from the Greek terms pharmakon, meaning drug, and logos, meaning debate or investigation. The study or debate of medication and its effects on the body is therefore pharmacology. Pharmacology is often divided into two primary branches: pharmacodynamics and pharmacokinetics. The study of pharmacodynamics revolves around how drugs interact with the body - their mech…

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Enzyme Induction, Enzyme Inhibition, Kinetics of Elimination

Reсent breаkthrоughs in mоleсulаr biоlоgy hаve enаbled а reсlаssifiсаtiоn оf drug metаbоlising enzymes bаsed оn their аminо асid sequenсe. This hаs led tо а better understаnding оf drug metаbоlism аnd drug interасtiоns. The mаjоrity оf these drug metаbоlising enzymes mаy be either induсed оr inhibited by drugs оr by extrаneоus substаnсes inсluding fооdstuffs, сigаrette smоke аnd envirоnmentаl роl…

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