Get access

Erectile Function in Two-Kidney, One-Clip Hypertensive Rats is Maintained by a Potential Increase in Nitric Oxide Production

Authors


Romulo Leite, PhD, Federal University of Ouro Preto—School of Pharmacy, Ouro Preto/MG—Brazil. Tel: +55 31 3559-1649; Fax: +55 31 3559-1628; E-mail: rl@ef.ufop.br

ABSTRACT

Introduction.  Hypertension is closely associated with erectile dysfunction (ED) as it has been observed in many experimental models of hypertension. Additionally, epidemiological studies show that approximately a third of hypertensive patients have ED.

Aim.  To test the hypothesis that the two-kidney, one-clip (2K-1C) rat model of hypertension displays normal erectile function due to increased nitric oxide (NO) production in the penis.

Methods.  Ganglionic-induced increase in intracavernosal pressure (ICP)/mean arterial pressure (MAP) ratio was used as an index of erectile function in 2K-1C and in normotensive sham-operated (SHAM) anesthetized rats. Cavernosal strips from hypertensive and normotensive rats were used for isometric tension measurement. The contraction induced by alpha-adrenergic agonist phenylephrine and the relaxation induced by the NO donor sodium nitroprusside (SNP) and by the Rho-kinase inhibitor Y-27632 were performed in the absence and in the presence of the NO synthase inhibitor Nω-nitro-L-arginine (L-NNA).

Results.  Changes in ICP/MAP induced by ganglionic stimulation were not different between 2K-1C and SHAM rats. The contractile response induced by phenylephrine as well as the relaxation induced by SNP or the Y-27632 were similar in cavernosal strips from both groups. However, in the presence of L-NNA, the relaxation induced by Y-27632 was significantly impaired in 2K-1C compared to SHAM.

Conclusions.  These data suggest that hypertension and ED could be dissociated from high levels of blood pressure in some animal models of hypertension. Erectile function in 2K-1C hypertensive rats is maintained in spite of the increased Rho-kinase activity by increased NO signaling. Linder AE, Dorrance AM, Mills TM, Webb RC, and Leite R. Erectile function in two-kidney, one-clip hypertensive rats is maintained by a potential increase in nitric oxide production. J Sex Med 2009;6(suppl 3):279–285.

Get access to the full text of this article

Ancillary