Chuanxiongzine relaxes isolated corpus cavernosum strips and raises intracavernous pressure in rabbits

Abstract

It has been shown that there are many Chinese traditional herbals that can enhance sexual activity. Chuanxiongzine is a vasoactive ingredient that has been isolated and purified from Ligusticum chuanxiong Hort. In previous studies, it has been found that chuanxiongzine was effective in relaxing rabbit corpus cavernosum smooth muscle. We determined the effects of chuanxiongzine on relaxation of isolated corpus cavernosum strips in vitro and on increase of intracavernous pressure (ICP) in vivo in rabbits. Chuanxiongzine caused a concentration-dependent relaxation of phenylephrine precontracted isolated corpus cavernosum strips (EC 50 1.58 Â 10 À4 mol l À1 ), which were endothelium independent and NO independent. However, the guanylyl cyclase inhibitor 1-H-[1,2,4] oxadiazolo [4,3-a] quinoxalin-1-one significantly shifted the chuanxiongzine concentration-response relationship to the right. Although there was no significant difference in the level of cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) in isolated corpus cavernosum strips treated with chuanxiongzine or vehicle, chuanxiongzine caused a significant rise in the level of cGMP and cAMP in isolated corpus cavernosum strips pretreated with the activator of adenylyl cyclase forskolin and the source of NO sodium nitroprusside. In an in vivo study, chuanxiongzine dose-dependently raised ICP after the intracavernous injection of its cumulative doses (0.5, 1, 2 and 5 mg kg À1 ). The ICP increased from baseline to 19.1±3.7, 24.8±2.1, 30.2 ± 4.8 and 39.7 ± 6.1 mm Hg, respectively, and the duration of tumescence ranged from 8.5 ± 2.8 to 22.9 ± 7.3 min. Our results show that chuanxiongzine can relax isolated corpus cavernosum strips of rabbits in vitro and increase ICP of rabbits in vivo, which is neither endothelium dependent nor NO dependent, but may be partly mediated by the inhibition of cAMP phosphodiesterase or cGMP phosphodiesterase.

Ligustrazine Inhibits Lung Phosphodiesterase Activity in a Rat Model of Allergic Asthma

“…Consistent with this, we found that ligustrazine treatment (40 and 80 mg/kg) decreased airway hyperreactivity in a rat OVA-induced model of asthma via suppressing the inflammation associated with OVA sensitization and subsequent aerosolized OVA challenge. Our results are in line with prior work demonstrating that ligustrazine can inhibit OVA-induced airway hyperresponsiveness, eosinophilia, goblet cell hyperplasia, airway remodeling, and Th2 cytokine production [ 22 , 31 , 32 , 34 – 36 ].…”

Ligusticum chuanxiongHort: A review of chemistry and pharmacology

“…TMP probably acts on an acceptor and vanillic acts on β1 acceptor. TMP could relax isolated corpus cavernosum strips and increase intracavernous pressure (ICP) of rabbits in vivo, which may be partly mediated by the inhibition of cAMP phosphodiesterase or cGMP phosphodiesterase (Xiao et al, 2010).…”

Traditional Chinese medical therapy for erectile dysfunction

“…Ligustrazine is a vasoactive component isolated from Ligusticum chuanxiong Hort and was shown to be effective in relaxing rabbit cavernosal smooth muscle. The effect was partly mediated by increasing the content of cAMP and cGMP ( 12 ).…”