Essential Pharmacology 1 Flashcards
What can be chemical messengers?
- Hormones
- Neurotransmitters
How can variety of responses in receptors be brought about?
- One cell can have receptors for many different chemical signals
- One cell can have several different receptors for the same chemical signal so that it triggers several different responses
What can receptors do?
They make an appropriate response e.g alter
- membrane permeability
- sensory activity
- metabolism
- rate of proliferation or differentiation
- contractile activity
When can a chemical messenger enter cells?
When it is lipid soluble
- hydrophobic molecules
- steroid hormones
Describe steroid hormones.
- Lipid soluble
- bind to intracellular receptors
- Often a transcription factor in the nucleus
- Alters rate of transcription
Describe NO.
- Lipid soluble
- Binds to soluble guanylyl cyclase
- Generates cGMP as second messenger which regulates cell activity.
What will you need for messengers that cannot enter the cell?
Cell surface receptors
What are the 4 tribes of cell surface receptors?
- Ionotropic receptors where the receptor is also and ion channel
- Receptors that function as enzymes
- Receptors that directly alter enzyme activity
- G protein couples receptors
What are the two types of enzymes you can get in an enzyme receptor?
- Tyrosine kinases which are involved in proliferation and differentiation
- Guanylyl cyclases in retina
What are receptors that interact with JAK kinases responsible for?
Protein synthesis
What are examples of ionotropic receptors?
- EPSPs
- IPSPSs
How many times do the G protein coupled receptors cross the plasma membrane?
7
What is the second messenger produced?
Adenylyl cyclase
What does adenylyl cyclase do?
Produced cAMP
What does cAMP do?
Regulates the activity of the enzyme PKA
