calcium channel clockers and diutetic drugs

Question 1

cardiomyocytes?

Answer 1

cacliuminduced calcium release by RyR on SR membrane

Question 2

smooth musce cells

Answer 2

gpcr - IP3R - Ca2+ CaM complex is activated and inhbits myosi light chain kinae - actin binds to myosin

Question 3

channels

Answer 3

closed - negatively polarised

open - positvely depolarised

inactive - membrane is very ++#

CCB block alphs subunit of L-type Ca2+ chanel when openm

Question 4

types of CCB?

Answer 4

dihydropyridines - nifedipine (hypertension and aingina)

phenylalkylamines - verapamil ( for cardiac arrythmias and angina)

Benzothiapenes - Diltiazem (for hypertension, angina and arrythmias)

Question 5

nifedipine

Answer 5

Question 6

diltiazem

Answer 6

Question 7

verapamil

Answer 7

Question 8

ccb contra and adr

Answer 8

Question 9

osmolarity and osmolaltiy?

Answer 9

osmolarity - moles of ions per litre of solution

osmolality - moles of ions poer kilogram of solvent

Question 10

mannitol

Answer 10

Question 11

acetazolamide

Answer 11

Question 12

fursemide

Answer 12

Question 13

bendroflumethiazide

Answer 13

Question 14

spironolactone

Answer 14

Question 15

k balance?

Answer 15

altering membrane potentials drive or inhibit k secretion in tubules.

furesimde and bendroflumethiazide trap na+ in the loop and DCT, delivering a high conc of Na+ to the collecting ducts downstream , which enhances K+ loss

potassium sparing diuretics block Na+ re-absorpion in the collecting duct only, which uncouples the membrane potentials that noiramlly drive K+ secretion

hypokalaemia can lowe the therapeutic index of drugs like digoxin and amiodarone. It can change ECg trces, flattened t wave, st depression, prolonged Pr interval