Catégories : Tous - receptors - pharmacodynamics - mechanism - activation

par Lindsay Treppa Il y a 5 années

194

Mind Map Assignment

The pharmacodynamics module explores various classical receptors and their functions. It delves into kinase-linked receptors, highlighting their structure, which includes membrane-localized domains linking extracellular domains to intracellular kinase domains.

Mind Map Assignment

Classical Receptors

Nuclear

Mechanism

heterodimerization with retinoid X receptor

often causes dissociation of co-repressor

co-activating protein

Heat shock proteins in cytoplasm

Dissociation from HSP

HRE on target genes

Recruit co-activators/repressors that effect gene transcription

Class II

Hybrid

Endocrine

RXR heterodimers

Lipid ligands

Intranuclear heterodimers

Class I

Endocrine ligands

Cytoplasmic homodimers

DNA recognition/binding domain

Ligand-gated ion channel

Examples
GABA Type A

Psychoactive drug targets

Binding of GABA to alpha/beta interface

Nicotinic ACh receptor

Central aqueous pore

Activation of channel

2 ACh binding regions

Pentameric complex

Sequence homology

Membrane localized

Ligand binding

Ion pore

Period of opening varies
Ligand or Agonist

Ion passage

Hyperpolarization or Depolarization

Kinase-linked

Related receptors
Cytokine

Associate with cytosolic tyrosine kinases

Serine/threonine kinases

GFR

Tyrosine kinases

Response to bacterial infection

GFs

Transduction
Cytokine binding to extracellular domain

Allows binding of independent cytoplasmic kinase

Activation of other proteins, transcription factors

Intrinsic kinase activity

proteins bound to activated intracellular domains

Recognizes phopshotyrosine domain

Links extracellular domain to intracellular kinase domain

GPCR

Desensitization
Receptor internalization
Receptor phosphorylation
G-proteins
Activation

2. Release subunits

Beta and gamma reunite with dissociated alpha, await recycle

Alpha subunit switches off by self-hydrolysis of GTP

1. GDP --> GTP

Alpha, beta, gamma subunits

associate with ligand-bound receptors

20 alpha isoforms

some activate, some inhibit

Subfamilies
Metaboropic glutamate

Calcium sensor

GABA

Secretin/glucagon

ligand binding domain

peptide hormones

Rhodopsin

extracellular helices or hoops bind ligands

Amine NT, NP, purines, cannabinoids

Structure
Intracellular g-protein coupling domain
7 transmembrane alpha helices
Membrane-localized

Pharmacodynamics Module 1