Rapeseed oil ingestion and exacerbation of hypertension-related conditions in stroke prone spontaneously hypertensive rats.

Abstract

Two groups of 20 stroke prone spontaneously hypertensive rats (SHRSP) at 5 weeks old were fed a diet containing 10 w/w% rapeseed (canola) oil or soybean oil as the only dietary fat, and given drinking water containing 1% NaCl. Life span of the canola oil group (62+/-2 days) was shorter than that of the soybean oil group (68+/-3 days). Stroke-related symptoms were observed in every animal, but the onset of those in the canola oil group, at 47+/-1 days after starting the administration was earlier than that in the soybean oil group, 52+/-2 days. Incidence of cerebral hemorrhage was similar in these groups, and no differences were found between lesions of organs in the groups. In another experiment, two groups of ten SHRSP at 5 weeks of age were fed the defatted diet and given canola oil or soybean oil by gavage at 10 w/w% of consumed food for 4 weeks without NaCl loading. After the 4-week administration, mean systolic blood pressure in the canola oil group and the soybean oil group were 233+/-2 and 223+/-0.3 mmHg, respectively. Phytosterol levels in both plasma and erythrocyte membranes reflected those contained in the oils ingested. Na(+), K(+)-ATPase activities in the brain, heart and kidney were enhanced in the canola oil group. These results indicate that promotion of hypertension-related deterioration in organs is likely to have relevance to the short life span in the canola oil group. Enhanced Na(+), K(+)-ATPase activity by phytosterols in the oil ingested may play a role in these changes.

• Authors: Yukiko Naito, Tomoko Nagata, Yuko Takano, Takashi Nagatsu, Naoki Ohara
• Journal: Toxicology (Toxicology) Vol. 187 Issue 2-3 Pg. 205-16 (May 03 2003) ISSN: 0300-483X [Print] Ireland
• PMID: 12699909 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Fatty Acids, Monounsaturated
• Phytosterols
• Plant Oils
• Rapeseed Oil
• Soybean Oil
• Sodium-Potassium-Exchanging ATPase

Topics

• Administration, Oral
• Animals
• Blood Pressure (drug effects)
• Brain (enzymology, pathology)
• Erythrocyte Membrane (chemistry, metabolism)
• Fatty Acids, Monounsaturated (administration & dosage, pharmacology)
• Hypertension (complications, mortality, physiopathology)
• Incidence
• Kidney (enzymology, pathology)
• Longevity (drug effects)
• Male
• Myocardium (enzymology, pathology)
• Phytosterols (blood)
• Plant Oils (administration & dosage, pharmacology)
• Rapeseed Oil
• Rats
• Rats, Inbred SHR
• Sodium-Potassium-Exchanging ATPase (drug effects, metabolism)
• Soybean Oil (administration & dosage, pharmacology)
• Stroke (etiology)