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Dúvidas denucci@gdenucci.com Arquivo SOHERJ-2004.ppt Site www.gdenucci.com. Ativadores de guanilato ciclase solúvel: uma nova classe de agentes anti-hipertensivos. NO-cGMP Biochemistry. ODQ. (-). L-NAME. GTP. sGC. (-). cGMP. NOS. PDE5. 5’GMP. (-). L-ARGININE. NO. PDE5
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Dúvidas denucci@gdenucci.com Arquivo SOHERJ-2004.ppt Site www.gdenucci.com
Ativadores de guanilato ciclase solúvel: uma nova classe de agentes anti-hipertensivos.
NO-cGMP Biochemistry ODQ (-) L-NAME GTP sGC (-) cGMP NOS PDE5 5’GMP (-) L-ARGININE NO PDE5 inhibitors
NO synthase NO donors YC – 1 BAY 58-2667 argine NO guanylyl cyclase cGMP-regulated Ion channels GTP cGMP cGMP-dependent protein kinases cGMP-regulated phosphodiesterases cellular effects
NO guanylyl cyclase GTP cGMP GMP cGMP cGMP-dependent protein kinase phospho diesterase 5 P Cellular effects
Tail-cuff pressure mmHg Weeks Basic Res Cardiol 91, 1996
Classification +1 or 2 foci of N or F (<500 mm) ++ >2 non-confluent (<500 mm) +++ confluent N or F (>500 mm)
Heart ischemia • L-NAME • 2K-1C 100 75 % 50 25 0 2w 4w 8w EPJ 287, 1995
Effect of enalapril pre-treatment (2 weeks) on L-NAME-induced hypertension 175 * * * * * * * 150 TCP (mmHg) 125 100 B 1 2 3 4 5 6 7 8 9 10 Weeks • Control L-NAME L-NAME + Enalapril • Enalapril
Heart ischemia 100 75 % 50 25 0 8w • L-NAME • Enalapril EPJ 287, 1995
NO hypertension Accompanied by kidney and heart disease Hypertension sensitive to ACE inhibitors Kidney disease sensitive to ACE inhibitors Heart ischemia not sensitive to ACE inhibitors
- NO and cGMP are involved in vasodilatation mechanism; - Glycerol trinitrate relaxes vascular smooth muscles by bioconversion to NO; - NO mediates vasodilatation by stimulating the soluble guanylate cyclase (sGC); - BAY 41-2272 is a pyrazolopyridine compound that potently stimulates sGC through this site by a mechanism that is independent of NO (Stasch et al., 2001). BAY 41-2272 (MW 360.40)
HO O N N Bay 58-2667 N OH O O O O O OH N N N YC-1 3-(5’-Hidroxymethyl-2’-furyl-1-1benzylindazole) ODQ 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one
Coronary blood flow Mean arterial blood pressure (ml min-1) (mm Hg) 50 40 30 20 10 0 0 -5 -10 -15 -20 -25 -30 3 10 30 100 3 10 30 100 Dose (μg kg-1 i.v.) Dose (μg kg-1 i.v.) Heart rate Oxygen saturation in coronary sinus (beats min-1) (%) 30 25 20 15 10 5 15 10 5 0 3 10 30 100 3 10 30 100 Dose (μg kg-1 i.v.) Dose (μg kg-1 i.v.)
Anaesthetised rat (i.v.) BAY-41-8543 Control 3 μg kg-1 i.v. 10 μg kg-1 i.v. 30 μg kg-1 i.v. 100 μg kg-1 i.v. 300 μg kg-1 i.v. Control 3 μg kg-1 i.v. 10 μg kg-1 i.v. 30 μg kg-1 i.v. 100 μg kg-1 i.v. 300 μg kg-1 i.v. 100 80 60 40 20 0 -20 -40 -60 -80 -100 40 20 0 -20 -40 -60 -80 Deviation in heart rate (beats/min) Deviation in mean blood pressure (mmHg) 0 5 10 15 20 25 30 35 0 5 10 15 20 25 30 35 Time (min) Time (min)
Anaesthetised rat (per os) Control 0,1 mg kg-1 p.o. 0,3 mg kg-1 p.o. 1 mg kg-1 p.o. Control 0,1 mg kg-1 p.o. 0,3 mg kg-1 p.o. 1 mg kg-1 p.o. 20 10 0 -10 -20 -30 -40 -50 -60 100 80 60 40 20 0 -20 -40 -60 -80 -100 Deviation in heart rate (beats / min) Deviation in mean blood pressure (mmHg) 0 20 40 60 80 100 120 140 0 20 40 60 80 100 120 140 Time (min) Time (min)
NO hypertension Accompanied by kidney and heart disease Hypertension sensitive to ACE inhibitors Kidney disease sensitive to ACE inhibitors Heart ischemia not sensitive to ACE inhibitors
Aims “ Evaluate the effects of BAY 41-2272 on the arterial blood pressure (MABP), heart weight index (HWI), left ventricular weight index (LVWI) and cardiomyocyte hypertrophy (Vv) induced by chronic L-NAME treatment in rats.”
N N F N N N NH2 STRUCTURE BAY 41-2272
Methods • Implant of radiotelemetry device into descending aorta; • Mean Arterial Blood Pressure (MABP) and Heart Rate acquired twice a week for 90 seconds during 8 weeks; • Heart and Left Venctricle Weight Indexes (HWI and LVWI) and cardiomyocyte volume density (Vv) were analysed to determine the cardiac and cardiomyocyte hypertrophy, respectively.
Animal groups - Control - L-NAME (20mg/rat per day) - L-NAME + BAY - BAY (10mg/kg per day) BAY was dissolved in DMSO 80% and administered by diary oral gavage. Control and L-NAME groups received DMSO 80% as a vehicle. (20mg/rat per day + 10mg/kg per day)
Effect of BAY 41-2272co-treatment on L-NAME-induced hypertension p<0.05 and p<0.01 compared to Control group ## p<0.01 compared to L-NAME group.
L-NAME + Control L-NAME BAY BAY Heart Rate ( bmp) 377 + 12 362 + 18 401 + 15 431 + 25* Body Weight 338.8 + 13.6 301.0 + 9.3* 324.0 + 15.1 295.7 + 16.0* Heart Weight # Index (HWI ; mg/g) 2.39 + 0.18 2.81 + 0.13* 2.46 + 0.21 2.48 + 0.26 Left Ventricle # Weight Index 1.12 + 0.15 2.08 + 0.19* 1.22 + 0.59 1.23 + 0.48 (LVWI ; mg/g) Heart Rate, Body Weight, Heart and Left Ventricle Weight Indexes after 8 weeks p<0.05 compared to Control group # p<0.01 compared to L-NAME group.
Left Ventricle Photomicrography - area of repairing fibrosis
Conclusion “ BAY 41-2272 significantly reduced arterial hypertension, cardiomyocyte hypertrophy and myocardial fibrosis induced by a 8-week treatment with L-NAME.”
Sildenafil (MW 474.46) BAY 41-2272 (MW 360.40) BAY 41-2272 induces HCC relaxation pEC50 Emax 6.71 0.05 111 5 6.85 0.06 117 5
0 BAY BAY + ODQ GTN 40 % Relaxation GTN + ODQ 80 120 -8 -7 -6 -5 log [BAY 41-2272] (M) 0 BAY BAY + ODQ GTN 40 % Relaxation GTN + ODQ 80 120 -8 -7 -6 -5 log [BAY 41-2272] (M) BAY 41-2272 induces CC relaxation Human Rabbit
Conclusão Ativadores da enzima guanilato ciclase solúvel apresentam interessante potencial terapêutico para tratamento de hipertensão arterial, isquemia miocárdica e disfunção erétil.