ace inhibitors

inodilators

calcium channel antagonists

nitric oxide donors

inodilator

inhibits PDE 3, increases CAMP and increases threshold to calcium without increasing myocardial oxygen

oral 2 X a day

excreted in bile

therefore  increase contraction in myocardium

vasorelaxation in vessel cells

positive inotrope

beta agonist

increase CAMP and protein kinase a and increase intracellular calcium

short half life-CRI

in acute heart failure

inhibit angiotensin converting enzyme cause vasodilation

Enalapril, Benzapril

watch potassium levels when using with potassium sparing diuretics, can cause hyperkalaemia

Benzapril-use more with animals with renal failure

prodrug-enalaprilat by serum esterase

inhibit activity-vasodilation

amlodipine- DOC for feline hypertension

usually NO released by endothelial cells to cause smooth muscle relaxation, but these supply it to guanyl cyclase. 

ex. Glyceryl trinitrate-first pass metabolism so apply on inside of pinna

pure venodilator

NO donor

can use in pulmonary oedema and heart failure

nitric oxide form in vascular smooth muscle

can get cyanide poisoning

light sensitive

negative chronotropy, to slow down HR

ex. digitalis

75% oral

half life over 30 hrs.

low doses are best ex. dobermans

afib

low dose if calcium channel blockers since highly protein bound 

class 1: Na channel effect

class 2: beta blockers

class 3: k channel

class 4: calcium channel antagonists

na channeleffect

1 A, B, C 

like LA effect, block Na channel

1 A-quinidine-not for dogs and cats, decreases conduction

1B- lidocaine- membrane stabilising, ERP A, increase without increasing ap duration

class 1 b

use in life threatening ER treatment for ventricular arrythmias

recovery from block is rapid

effective refractory period

A or B

A-increase ERP without increasing AP duration

b: increasing AP duration

beta blockers

atenolol-longer acting

esmolol-shorter acting-metabolised by RBC esterases

manages EAD and DADs well

slow down conduction speed

tachyarrythmias, HCM in cats

hypotension, bradycardia

can change the number of beta receptors in the heart

K channel effects

ex. sotalol

beta blocker and k channel blocker effects

prolongs AP duration

lower AV conduction and refractoriness

calcium channel antagonists

amlodipine-feline hypertension

blocks slow ca channels

vagolytic- atropine

beta 2 agonist- terbutaline

pacemaker

1. chemical gradient

2. with an organic solute or phosphate

3. exchanged for a positive ion

4. exchanged for cl

5. exchanged for k and 2cl

1. thiazides

2. loop 

3. aldosterone and potassium sparing

4. osmotic

5. carbonic anhydrase inhibitors

chlorthiazide, hydrochlorthiazide

bind to Na and cl co transoport system in DCT, inhibiting the reabsorption of Na and H20

manage oedema

combo with frusomide

DI nephrogenic form. 

frusemide

highly effective

high K loss

inhibit K and 2cl co transoport with Naa nd also reduce hypertonicity to prevent reabsorption in descending loop and collecting tubule

vasodilatory effect

rapid onset - 30min-1hr, duration 3-6hrs

need to be careful when using with ace inhibitors- can cause hyperkalaemia

spironolactone- lose na and water, retain k

Amiloride- prevent reabsorb of Na, 24 hr duration, slow onset

combo with frusomide

combo prep with a thiazide too 

mannitol

freely filtered through glomerulus

get conc. in PCT, then water stays in there, also reduce hypertonicity and prevent reabsorbtion of water from descending loop of henle

acute renal failure to restore urine production

reduce CSF pressure

IV slow infusion

by inhibiting carbonic anhydrase, bicarb, na, K stay in lumen together, increase in urine volume

acetazolamide- treat glaucoma