The effect of DA-8159, a novel PDE5 inhibitor, on erectile function in the rat model of hypercholesterolemic erectile dysfunction.

Abstract

This study examined the effects of a new phosphodiesterase type 5 inhibitor, DA-8159, on erectile function associated with hypercholesterolemia. First of all, in order to investigate whether chronic administration of DA-8159 prevents the development of erectile dysfunction associated with hypercholesterolemia, male SD rats were divided into four groups (normal control, hypercholesterolemic control, DA-8159 5 or 20 mg/kg/day). Over a 5-month period, the animals were fed a 2% cholesterol diet and administered DA-8159 orally once a day. After 5 months, the electrostimulation-induced penile erection and the vascular function using acetylcholine-induced vasodilation with endothelium-intact aortic rings were examined. Furthermore, the plasma lipid profiles, endothelin and N(G),N(G)-dimethylarginine (asymmetrical dimethylarginine, ADMA) concentrations were measured. In order to investigate the acute treatment effect of DA-8159 on the erectile function in an established hypercholesterolemic model, additional animals were given a 2% cholesterol diet for 5 months without DA-8159. At the end of 5 months, the rats were divided into three groups (hypercholesterolemic control, DA-8159 0.3 or 1 mg/kg). DA-8159 was administered intravenously 1 min prior to the intracavernous pressure (ICP) measurement. In a chronic treatment study, while the hypercholesterolemic control showed a significantly lower erectile function, vascular reactivity, and increased plasma cholesterol, endothelin and ADMA concentration, the chronic DA-8159 treatment clearly restored the erectile responses by electric stimulation, preserved the potential of thoracic aortic relaxation in a dose-dependent manner, and significantly decreased the plasma endothelin and ADMA concentrations. In an acute treatment study, DA-8159 induced a dose- and frequency-dependent increase in ICP. The ICP/BP ratio and the corresponding AUC values, and the detumescence time were also significantly increased compared to the hypercholesterolemic control. These results suggest that DA-8159 is beneficial for erectile dysfunction in a rat hypercholesterolemic model and provided a rationale for the potential use of DA-8159 for treating erectile dysfunction secondary to hypercholesterolemia.

• Authors: K K Kang, J Y Yu, M Yoo, J W Kwon
• Journal: International journal of impotence research (Int J Impot Res) 2005 Sep-Oct Vol. 17 Issue 5 Pg. 409-16 ISSN: 0955-9930 [Print] England
• PMID: 15920460 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Endothelins
• Lipids
• Phosphodiesterase Inhibitors
• Pyrimidines
• Sulfonamides
• dimethylarginine
• Arginine
• 3',5'-Cyclic-GMP Phosphodiesterases
• Cyclic Nucleotide Phosphodiesterases, Type 5
• Pde5a protein, rat
• udenafil
• Acetylcholine

Topics

• 3',5'-Cyclic-GMP Phosphodiesterases (antagonists & inhibitors)
• Acetylcholine (pharmacology)
• Animals
• Aorta (drug effects, physiology)
• Arginine (analogs & derivatives, blood)
• Cyclic Nucleotide Phosphodiesterases, Type 5
• Disease Models, Animal
• Dose-Response Relationship, Drug
• Endothelins (blood)
• Erectile Dysfunction (drug therapy, etiology)
• Hypercholesterolemia (complications)
• In Vitro Techniques
• Lipids (blood)
• Male
• Muscle Relaxation (drug effects)
• Penile Erection (drug effects, physiology)
• Phosphodiesterase Inhibitors (pharmacology)
• Pressure
• Pyrimidines (pharmacology)
• Rats
• Rats, Sprague-Dawley
• Sulfonamides