Dynamics Flashcards
(21 cards)
who have affinity to receptors agonist or antagonist
both of them
Receptor
mediated “4”
1
. Ligand gated ion channels fast neurotransmitters)
3
. Receptors Linked to Tyrosine Kinase Enzymes
2
. G protein Coupled Receptors slow neurotransmitters)
4
Intracellular Receptors Regulating
Transcription very slow)
Ligand gated ion channels eg.
cholinergic nicotinic receptors
G protein Coupled Receptors
alpha and beta adrenoreceptors
Receptors Linked to Tyrosine Kinase Enzymes eg.
insulin receptors
Intracellular Receptors Regulating
Transcription
steroid receptors
what happens to the muscke when Na+ influx due to stimulation of ligand gated ion channel
depolarization skeletal muscle contraction
types of G protein receptors
Gs, Gi, Gq
what does G protein consists of
protein is a trimer (α, β and γ).
movable and fixed parts in G protein
β
and γ are fixed in cell membrane. But α subunit move
when we can say that G protein is active
when GDP is GTP
What is the sequence of Gq?
GDP→GTP activates enzyme PLC “phospholipase C” on cell membrane →breaks PIP2 to DAG and IP3
DAG activates PKC
IP3 activates Ca influx from SR “sarcoplasmic reticulum”
What is the sequence of Gs?
GDP→GTP activates adenylyl cyclase converts ATP→cAMP which activates PKA which phosphorylates
What is the sequence of Gi?
GDP→GTP inhibits adenylyl cyclase which inhibits PKA which and inhibit phosphorylation
which enzyme activates in Gq
PLC and PKC
which enzyme activates in Gq
PKA
What is the 2nd messenger in Gs?
cAMP
What is the 2nd messenger in Gq?
DAG & IP 3
what is the sequence of Tyrosine Kinase receptors
receptors binder (insulin) activates tyrosine kinase receptor→ phosphorylates tyrosine residues→ cellular response.
What is the 2nd messenger in tyrosine kinase receptor?
Phosphorylated Tyrosine Residues
receptors for hydrophilic large drugs.
ligand gated ion channel
G protein coupled receptors
Tyrosine kinase receptors
