HISTAMINE.pptx

# B. Pharm 5 Semester
# Medicinal Chemistry -2
# Pharmacology - 2
# Histamine
# Introduction
# Structure of Histamine
# Synthesis of Histamine
# Storage of Histamine
# Release of Histamine
# Flowchart - Histamine Release
# Mechanism of Antigen-Antibody Reaction Induced Release of Histamine From Mast Cell
# Function Of Histamine
# Pharmacological Action of Histamine
- CNS
- Heart
- Blood Vessels

1. ANTI - HISTAMINIC AGENTS BY T.GOKUL B.PHARM PART – 1 TOPICS UNDERCOMES HISTAMINE INTRODUCTION STRUCTURE SYNTHESIS STORAGE RELEASE FUNCTION PHARMACOLOGICAL ACTION B.PHARM 5 SEMESTER MEDICINAL CHEMISTRY - 2 PHARMACOLOGY - 2

2. HISTAMINE INTRODUCTION Histos – Tissue Synonym : Tissue Amine Histamine Is An Autocoid (Autos – Self, Akos – Remedy ; Which Means Its Acts Similarly To A Local Hormone, Near Its Site Of Synthesis) Important Inflammatory Mediator. Plays An Important Role In Inflammation Anaphylaxis Allergies Gastric Acid Secretion Drug Reaction Histamine Is A Biological Amine, Present In Animal And Plant Tissues.

3. PRESENT MOSTLY IN MAST CELLS SKIN LUNGS GIT MUCOSA NON – MAST CELL HISTAMINE BRAIN GASTRIC MUOSA STRUCTURE IUPAC Name : 4 – (2 – Amino Ethyl ) Imidazole Common Name : Imidazole Ethylamine Histamines Are Nitrogen Containing Organic Compounds Belonging To The Group Of Amines

4. SYNTHESIS HISTAMINE IS SYNTHESIZED FROM NATURALLY OCCURING -AMINO ACID HISTIDINE BY THE PROCESS OF DECARBOXYLATION . SITE : PRIMARILY TAKE PLACE IN MAST CELLS & BASOPHILS ENZYME : L – HISTIDINE DECARBOXYLASE

5. STORAGE Stored In Mast Cell In Complex With Heparin (Anticoagulant). Basophiles In Complex With Chondrotin . RELEASE Histamine Is Released Because Of The Interaction Of An Antigen With IgE Antibodies On The Most Cell Surface. Mild Release Of Histamine In The Body Leads To Allergic Reaction. Extreme Release Of Histamine In The Body Leads To Anaphylatic Shock – Fatal.

6. Antigen + IgE Antibody In Mast Cells Activate Tyrosine – Protein Kinase Phosphorylation And Activation Of Phospholipase C  Phosphatidyl Inositol Triphosphate Iniositol Triphosphate Triggers Ca 2+ Ca 2+ Induces The Fusion Of Granule Membrane Results In Release Of Granule Contents In Granules Postiviely Charged Histamine Complexed With Negatively Charged Protein. Cationic Exchange With Extracellular Na + Sets Histamine Free And Acts On Target Cell FLOWCHART - HISTAMINE RELEASE

7. Mechanism Of Antigen – Antibody Reaction Induced Release Of Histamine From Mast Cell

8. FUNCTION Histamines Has Various Functions In Body Such As Mediator Of Inflammation And Local Hormone Response. Regulating Physiological Function In The Gut. Acting As A Neurotransmitter. Important Role In The Regulation Of Gastric Acid Secretion. PHARMACOLOGICAL ACTIONS OF HISTAMINE CNS No BBB Penetration On Intracerebrovascular Injection: Increase In BP, Cardiac Stimulation Vomiting, ADH Release

9. HEART Insitu Heart – No Prominent Action Isolated Heart – Increase In Rate & FOC BLOOD VESSELS Dilation Of Smaller Blood Vessels S.C. Injection – Heart, Flushing, Increase In HR & CO Rapid IV Injection – Decrease BP Intradermal Injection : (Triple Response) Red Spot – Capillary Dilation Wheal – Exudation Of Fluid From Capillaries And Venules Flare – Arteriolar Dilation