Systemic antioxidant properties of L-carnitine in two different models of arterial hypertension.
In spite of a wide range of drugs being available in the market, treatment of arterial hypertension still remains a challenge, and new therapeutic strategies could be developed in order to improve the rate of success in controlling this disease. Since oxidative stress has gained importance in the last few years as one of the mechanisms involved in the origin and development of hypertension, and considering that L-carnitine (LC) is a useful compound in different pathologies characterized by increased oxidative status, the aim of the present study was to investigate the systemic antioxidant effect of LC and its correlation to blood pressure in two experimental models of hypertension: (1) spontaneously hypertensive rats (SHR) and (2) rats with hypertension induced by N(omega)-nitro-L-arginine methyl ester (L-NAME). Treatment with captopril was also performed in SHR in order to compare the antioxidant and antihypertensive effects of LC and captopril. The antioxidant defense capacity, in terms of antioxidant enzyme activity, glutathione system availability and plasma total antioxidant capacity, was measured in both animal models with or without an oral, chronic treatment with LC. All the antioxidant parameters studied were diminished in SHR and in L-NAME-treated animals, an alteration that was in general reversed after treatments with LC and captopril. In addition, LC produced a significant but not complete reduction of systolic and diastolic blood pressure levels in these two models of hypertension, whereas captopril was able to normalize blood pressure. Both LC and captopril prevented the reduction in nitric oxide (NO) levels observed in hypertensive animals. This suggests a decrease in the systemic oxidative stress and a higher availability of NO induced by LC in a similar way to captopril's effects, which could be relevant in the management of arterial hypertension eventually.
Mate
Alfonso
A
Departamento de Fisiología y Zoología, Facultad de Farmacia, Universidad de Sevilla, CL Profesor García González, 2, 41012 Sevilla, Spain. mate@us.es
Miguel-Carrasco
José L
JL
Monserrat
María T
MT
Vázquez
Carmen M
CM
D000818:Animals; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D000975:Antioxidants / Q000378:metabolism / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D002216:Captopril / Q000627:therapeutic use*; D002331:Carnitine / Q000627:therapeutic use*; D005978:Glutathione / Q000378:metabolism; D005979:Glutathione Peroxidase; D005980:Glutathione Reductase / Q000378:metabolism; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D019331:NG-Nitroarginine Methyl Ester; D009566:Nitrates / Q000097:blood; D009573:Nitrites / Q000097:blood; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY
D000959:Antihypertensive Agents; D000975:Antioxidants; D009566:Nitrates; D009573:Nitrites; D002216:Captopril; D005979:Glutathione Peroxidase; D005980:Glutathione Reductase; D005978:Glutathione; D002331:Carnitine; D019331:NG-Nitroarginine Methyl Ester