Which of the following drug is a renin inhibitor?

ANSWER: (D) AliskirenREF: Goodman Gillman page 525, KDT 6th edition page 482, Katzung 12th ed page 190, 300Repeat from Pharmacology June 2010, December 2008RENIN INHIBITORSCleavage of angiotensinogen by renin is the rate-limiting step in the formation of ANG II and thus represents a logical target for inhibition of the renin-angiotensin system. Drugsthat inhibit renin have been available for many years but have been limited by low potency, poor bioavailability, and short duration of action. However, a new class of nonpeptide, low- molecularweight, orally active inhibitors has recently been developed. Aliskiren, a renin inhibitor recently approved for hypertension, is in clinical trials for heart failure. Preliminary results suggest an efficacy similar to that of ACE inhibitors. Aliskiren is contraindicated in pregnancy.INHIBITION OF RENIN-ANGIOTENSIN SYSTEMSympatheticblockersPlasma renin activity is increased by reflex increase in sympathetic discharge. Sympathetic blockers decreases renin release.Clonidine decreases central sympathetic outflow and thus will decrease plasma renin activity.B blockersadrenergic neurone blockers,central sympatholytics:* Clonidine (a2 agonist)* Guanfacine (a2 agonist)* Methyldopa (a2 agonist)* Moxonidine (imidazoline receptor agonist)* Prazosin (a1, antagonist)* Rescinnamine (ACE inhibitor)* Reserpine (VMAT inhibitor)* Rilmenidine (imidazoline receptor agonist)RenininhibitorsRenin inhibitory peptides and renin specific antibodies block renin action-interferes with generation of A-I from angiotensinogen. (rate limiting step}Aliskiren (Oral: 150, 300 mg tablets)Angiotensin converting enzyme (ACE) inhibitorsPrevent generation of the active principle A-IICaptopril and enaiaprilAngiotensinreceptor(ATI)antagonistsBlock the action of A-II on target cellsLosartan, valsartan, eprosartan, irbesartan, candesartan, olmesartan , and telmisartanAldosteroneantagonistsBlock mineralocorticoid receptorseplerenonespironolactone