Antihypertensive potential and mechanism of action of astaxanthin: III. Antioxidant and histopathological effects in spontaneously hypertensive rats

Biol Pharm Bull. 2006 Apr;29(4):684-8. doi: 10.1248/bpb.29.684.


We investigated the effects of a dietary astaxanthin (ASX-O) on oxidative parameters in spontaneously hypertensive rats (SHR), by determination of the level of nitric oxide (NO) end products nitrite/nitrate (NO2-/NO3-) and lipid peroxidation in ASX-O-treated SHR. Oral administration of the ASX-O significantly reduced the plasma level of NO2-/NO3- compared to the control vehicle (p<0.05). The lipid peroxidation level, however, was reduced in both ASX-O- and olive oil-treated groups. We also analyzed the post-treatment effects of ASX-O on the vascular tissues by examining the changes in the aorta and coronary arteries and arterioles. The dietary ASX-O showed significant reduction in the elastin bands in the rat aorta (p<0.05). It also significantly decreased the [wall : lumen] aerial ratio of the coronary arteries. These results suggest that ASX-O can modulate the oxidative condition and may improve vascular elastin and arterial wall thickness in hypertension.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antihypertensive Agents / pharmacology*
  • Antioxidants / pharmacology*
  • Aorta, Thoracic / pathology
  • Blood Pressure / drug effects
  • Coronary Vessels / pathology
  • Elastin / metabolism
  • Heart / drug effects
  • Heart Rate / drug effects
  • Hypertension / drug therapy*
  • Hypertension / pathology
  • Lipid Peroxidation / drug effects
  • Male
  • Muscle, Smooth, Vascular / drug effects
  • Myocardium / pathology
  • Nitric Oxide / metabolism
  • Rats
  • Rats, Inbred SHR
  • Xanthophylls / pharmacology


  • Antihypertensive Agents
  • Antioxidants
  • Xanthophylls
  • Nitric Oxide
  • astaxanthine
  • Elastin