伐地那非 (Levitra, Staxyn)

概览

Vardenafil is a phosphodiesterase 5 inhibitor used to treat erectile dysfunction.

作用机制

Vardenafil inhibits cyclic guanosine monophosphate (GMP) specific phosphodiesterase type 5 (PDE5), which is responsible for the degradation of cyclic GMP in the corpus cavernosum located around the penis. Penile erection during sexual stimulation is caused by increased penile blood flow resulting from the relaxation of penile arteries and corpus cavernosal smooth muscle. This response is mediated by the release of nitric oxide (NO) from nerve terminals and endothelial cells, which stimulates the synthesis of cyclic GMP in smooth muscle cells. Cyclic GMP causes smooth muscle relaxation and increased blood flow into the corpus cavernosum. The tissue concentration of cyclic GMP is regulated by both the rates of synthesis and degradation via phosphodiesterases (PDEs), and the most abundant PDE in the human corpus cavernosum is PDE5. Therefore, the inhibition of PDE5 by vardenafil enhances erectile function by increasing the amount of cyclic GMP.

适应症

Vardenafil is indicated for the treatment of erectile dysfunction.

• Erectile Dysfunction