Telmisartan

Etki Mekanizması

Telmisartan selectively blocks the angiotensin II type 1 (AT1) receptor, preventing angiotensin II from exerting its vasoconstrictive, aldosterone-secreting, and pro-fibrotic effects. By antagonizing AT1, telmisartan lowers systemic vascular resistance and blood pressure while simultaneously reducing pathological cardiac and vascular remodeling. This is particularly relevant for AAS users, where supraphysiological androgen levels stimulate the renin-angiotensin-aldosterone system (RAAS) and promote myocardial fibrosis and left ventricular hypertrophy. Telmisartan also has the longest half-life of any ARB (approximately 24 hours), providing consistent receptor blockade throughout the dosing interval. Its unique partial agonism of PPAR-gamma -- a nuclear receptor involved in glucose and lipid metabolism -- distinguishes it from other ARBs. PPAR-gamma activation enhances insulin sensitivity, improves adiponectin secretion, reduces visceral fat accumulation, and exerts anti-inflammatory effects. Additionally, telmisartan demonstrates nephroprotective properties by reducing intraglomerular pressure and proteinuria, and has been shown in the ONTARGET trial to provide cardiovascular protection comparable to the ACE inhibitor ramipril in high-risk patients.