The administration of folic acid improves erectile function and reduces intracavernosal oxidative stress in the diabetic rabbit

BJU Int. 2009 Jan;103(1):98-103. doi: 10.1111/j.1464-410X.2008.07911.x. Epub 2008 Sep 3.


Objective: To test the possibility that folic acid (FA) may be a means of treating erectile dysfunction (ED) in diabetes mellitus (DM), by studying the effect of FA administration to DM rabbits on cavernosal function and intrapenile oxidative stress.

Materials and methods: To investigate the effect of administering FA to DM rabbits on erectile function and oxidative stress the formation of superoxide (O(2)(-)), 8-isoprostane F(2 alpha) (8-IPF(2 alpha)) and prostacyclin (as 6-keto-PGF(1 alpha)) were assessed, as well as carbachol- and electrical field stimulated (EFS) relaxation and p47(phox) content (active component of NADPH oxidase complex). Non-ketotic DM was induced in New Zealand rabbits with alloxan and FA administered orally daily for 1 month. Rabbits were killed, penises excised and segments prepared. These were mounted in an organ bath and relaxation elicited with carbachol or EFS. O(2)(-) release was measured spectrophotometrically, p47(phox) expression by Western blotting and 8-IPF(2 alpha) and 6-keto-PGF(1 alpha) formation by enzyme-linked immunosorbant assay. Blood was collected for measurement of homocysteine, red blood cell (RBC) folate and glucose.

Results: In cavernosal tissue from DM rabbits, carbachol-and EFS-induced relaxation was significantly impaired compared with the untreated controls. O(2)(-) release, p47(phox) expression and 8-IPF(2 alpha) formation were all enhanced and 6-keto-PGF(1 alpha) formation reduced compared with the controls. All these effects were reversed by FA. Plasma total homocysteine was reduced and RBC folate elevated.

Conclusions: The administration of FA may constitute a strategy for reducing ED in patients with DM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antioxidants / administration & dosage
  • Antioxidants / pharmacology*
  • Blotting, Western
  • Diabetes Mellitus, Experimental / complications
  • Drug Evaluation, Preclinical
  • Erectile Dysfunction / drug therapy*
  • Erectile Dysfunction / physiopathology
  • Folic Acid / administration & dosage
  • Folic Acid / pharmacology*
  • Male
  • Oxidative Stress / drug effects*
  • Oxidative Stress / physiology
  • Penile Erection / drug effects*
  • Penile Erection / physiology
  • Rabbits
  • Treatment Outcome
  • Vasodilator Agents / administration & dosage
  • Vasodilator Agents / pharmacology*


  • Antioxidants
  • Vasodilator Agents
  • Folic Acid