Neurotransmitters

Question 1

Which GLUT’s in brain?

Answer 1

GLUT1 for endothelial cells, GLUT3 for neurons

Question 2

What Fats can cross BBB? What properties do BBB cells have?

Answer 2

EFA’s can cross BBB, but not non-essential FA’s

Tight junctions, no pinocytosis

Question 3

Catecholamine NT’s

Answer 3

DA, NE, Epi

Question 4

RLS for Catecholamine synthesis? How is it regulated

Answer 4

Tyrosine Hydroxylase

• inhibited by DA and NE
• increased by cAMP dependent phosphorylation

Question 5

Path for Catechol. Synth

Answer 5

Tyr – DOPA—DA–NE—EPI

Question 6

Formation of DA needs…

Answer 6

B6

Question 7

Formation of NE needs…

Answer 7

Vitamin C

Question 8

Formation of Epi needs…

Answer 8

SAM

Question 9

2 enzymes that breakdown NE and Epi

Answer 9

MAO and COMT

Question 10

COMT requires…

Answer 10

SAM

Question 11

Epinephrine acts via

Answer 11

B2 receptors, stimulating G protein cascade that involves Ca++ and PKC

Question 12

Melanin formation dependent on what enzyme

Answer 12

Tyr Hydroxylase (Low pigment if deficient)

Question 13

Conversion of Tyrosine to Melanin is ___ dependent

Answer 13

Copper

Question 14

Pheochromocytoma… what is it? Dx? Tx?

Answer 14

Increased NE or Epi from adrenal tumor

Dx from METANEPHRINE in urine

Tx = surgery or A/B receptor antagonists

Question 15

Catechol. Inactivation

Answer 15

NE–Mao–DIHYDROXYMANDELIC acid—COMT—VMA

NE – COMT–NorMetanephrine–MAO–VMA

Question 16

Levadopa converted to DOPA by

Answer 16

L amino acid decarboxylase

Question 17

Serotonin Synthesis enzymes (2)

Answer 17

Tryptophan Hydroxylase

Dopa Decarboxylase

Question 18

Serotonin converted to ____ or _____. (with the two enzymes)

Answer 18

5OH-Acetaldehyde by MAO-A

Melatonin via SAM methylation of N-Acetyl Serotonin

Question 19

Histamine formation occurs via

Answer 19

Histidine Decarboxylation (requires B6)

Question 20

SSRI examples

Answer 20

Prozac, Zoloft, Celexa

Question 21

Histamine functions

Answer 21

Vasodilator, constrict bronchioles, increase HCl secretion, sleep regulation

Question 22

Histamine is converted to what two things? Where?

Answer 22

Imidizole in the periphery by DIAMINE OXIDASE

Methlhistamine in brain

Question 23

Choline synthesis needs…

Answer 23

3 methyl transferase reactions (via SAM and PE)

Question 24

Ach-ase inhibitors: examples and function

Answer 24

Sarin, Parathion

Form covalent bonds with SERINE in the active site

Tx = atropine

Question 25

Ach activates_____ receptors

Answer 25

Muscarinic

Question 26

Pyridostigmine is a

Answer 26

Ach-esterase inhibitor used for M.G. Treatment

Question 27

Nitric Oxide compound type

Answer 27

Free radical diatomic gas

Question 28

Formation of NO

Answer 28

Arg + NADPH ——> Citrullline + NADP + NO

Question 29

Cofactors in NO synthesis (NO SYNTHASE)

Answer 29

FAD, FMN, Cytochrome-like heme prosthetic groups

Question 30

NOS1

Answer 30

Neuronal

Increased by NMDA stimulation via Glutamate

Question 31

NOS2

Answer 31

Macrophage-induced

Question 32

NOS3

Answer 32

Endothelial (constitutive)

Question 33

NO mechanism

Answer 33

Stimulates Guanylate cyclase –> cGMP

stimulates relaxation