Across
- 2. both B-1 and b-2 receptors are __ proteins, closely linked to the enzyme adenylyl cyclase. cAMP levels INCREASE (A-2 adrenoceptors (Gi proteins) also use adenylyl cyclase).
- 3. alpha ___ adrenoceptors are located at PRE junctional sites on nerves (inhibit transmitter release) – agonists are clonidine and XYLAZINE – a vet sedative. Antagonist: YOHIMBINE (reverses effects of xylazine).
- 4. noradrenaline is MOST selective for ______-1 receptors (constrict blood vessels, GIT sphincters, dilate pupil). LEAST selective for beta-2 receptors (dilate bronchi and skeletal muscle vessels). Not as useful as a DRUG as adrenaline.
- 5. this drug is a partial agonist at alpha-2 adrenoceptors on PREjunctional nerve membranes. It inhibits transmitter release, causes some vasoconstriction, but decreases heart rate.
- 6. adrenoceptors are G-protein coupled receptors with ______ membrane spanning segments.
- 7. clonidine is a non-catecholamine. It causes vasoconstriction of blood vessels (not those going to skeletal muscle). Its effects are inhibited by phentolamine. What type of drug is it? (alpha/beta (first word) agonist/antagonist)?
- 9. the neurotransmitter _____________ does not make a good drug because is has restricted diffusion and is broken down in the synapse.
- 12. unlike with Gs b-1 and b-2 receptors that also use adenylyl cyclase, the Gi a-2 receptor in prejunctional neurons _________ cAMP levels. (inhibitory)
- 13. dobutamine, a beta one agonist, is used to treat heart ______ (increases rate and force of contraction.
- 14. a drug used to treat hypertension (beta one antagonist – decreases rate/force of contraction). Does not have side effect of worsening asthma like the beta one AND two antagonist propranolol. Ends in olol as well.
Down
- 1. a-1 adrenoceptors are G-protein coupled Gq receptors that are linked to the enzyme _______________ (use IP3 and DAG as second messengers)
- 2. adrenoceptors are _ _______ coupled receptors.
- 4. alpha 1 adrenoceptors are located at POST junctional sites on Blood vessels, GIT and pupil. __________: phenylephrine. Antagonist: prazosin.
- 8. a-2 receptors, on prejunctional nerve sites, are Gi proteins. They ______ nerve transmission. Linked to adenylyl cyclase (like B1 and B2 adrenoceptors).
- 10. alpha ___ adrenoceptors are located at POST junctional sites on Blood vessels, GIT and pupil. Agonist: phenylephrine. Antagonist: prazosin.
- 11. this drug/hormone is very effective at stimulating b-1 (heart/kidney), b-2 (skeletal muscle blood flow, bronchi dilation), a-1 receptors (vasoconstriction of unneeded BVS, dilate pupil, constrict GIT sphincters). All the features of a flight/fight response. Very useful as a drug in emergency situations esp allergic rxns.