NTs 2

Question 1

DA receptors: structure? two groups and how they work?

Answer 1

all heptahelical, no ionotropic. D1 like = D1 and D5 couple to Gq and Gs. D2 (D2, 3, 4) couple to Gi

Question 2

D2 receptors function

Answer 2

major autoreceptor, but can also be found postsynpatically

Question 3

D2 antagonists used for

Answer 3

antiemetic agents, act in chemoreceptor trigger zone in area postrema

Question 4

D2 autoreceptor activation can alter transmission in 3 ways

Answer 4

suppress presynaptic Ca channel current. hyperpolarize presynpatic terminals via activating GIRK channels. direct effects on release process.

Question 5

correlation between D2 antagonist affinity and?

Answer 5

antipsychotic action. higher affinity = need lower dose for antipsych effect

Question 6

3 dopamine systems

Answer 6

nigrostriatal. tuberoinfundibular. mesolimbic.

Question 7

nigrostriatal: main idea + what areas

Answer 7

parkinson’s: substantia nigra pars compacta to caudate/putamen neostriatum

Question 8

tuberoinfundibular: main idea + what areas

Answer 8

arcuate nucleus to pituitary: for prolactin

Question 9

mesolimbic: main idea + what areas

Answer 9

for addiction and reward: ventral tegmental area, nucleus accumbens, cingulate and frontal cortex

Question 10

nigrostriatal DA system is involved in? what disease and what drug?

Answer 10

control of mvt, learning of motor programs. loss of DA neurons in SN = Parkinson’s. L-DOPA to replace DA

Question 11

tuberinfundibular system: function? effect of antipsychotic drugs?

Answer 11

hypothalamic arcuate nucleus cells project and inhibit release of PRL from pituitary. antipsych drugs increase PRL, produce hyperprolactinemia and lactation

Question 12

bromocriptine: what and effect

Answer 12

D2 agonist. mimics DA. inhibits prolactin release so treats hyperprolactinemia

Question 13

what DA receptors in nucleus accumbens? do what? role?

Answer 13

D1, D2, D3 receptors inhibit spiny projection neurons. involved in cognitive and emotive functions; reward and addiction

Question 14

antipsychotic drugs and mesolimbic?

Answer 14

D2 antagonists = antipysch drugs. but possibility of PD like side effects

Question 15

serotonin: receptors - types and general structure

Answer 15

metabotropic G protein coupled: 5HT1, 2, 4, 5 - 7. also have 5HT3 = cation channel

Question 16

serotonin: cell bodies where? peripheral roles?

Answer 16

cell bodies in raphe nuclei. peripheral role in enteric NS

Question 17

serotonin: how to terminate action? drug?

Answer 17

transporter/uptake system. SSRIs like fluoxetine / prozac to treat depression

Question 18

serotonin syndrome: what three categories of effects

Answer 18

cognitive, autonomic and somatic

Question 19

serotonin syndrome: cognitive effects

Answer 19

headache, migraine. mental confusion. hallucinations (like LSD which agonizes 5HT2). coma (5HT involved in sleep)

Question 20

serotonin syndrome: autonomic effects

Answer 20

shivering, sweating, hyperthermia. hypertension. tachycardia. nausea, diarrhea (hyperkinetic effect on gut). mydriasis = pupil dilation

Question 21

somatic effects from serotonin syndrome: 3

Answer 21

myoclonus = muscle twitching, hyper reflexia. tremor

Question 22

nitric oxide: receptor? effect? 3 isoforms?

Answer 22

guanylyl cyclase - makes cGMP. neuronal, endothelial and inducible isoforms

Question 23

functions of NO

Answer 23

vasodilation, nonadrergic noncholinergic intestinal relaxation, erection, neuro toxicity and plasticity, central autonomic functions

Question 24

NO pathway of synthesis

Answer 24

endothelial cell: ACh/bradykinin, substance P activates receptors = increase in Ca. calmodulin activates NOS to produce NO + citruilline from arginine.

Question 25

NO pathway of action

Answer 25

NO diffuses from endothelial cell into smooth muscle cell. activates GC = makes cGMP = relaxation