title: Effects of 1,8-cineole on hypertension induced by chronic exposure to nicotine in rats.
abstract: OBJECTIVE
  The monoterpenic oxide 1,8-cineole is a major component of many essential oils. We investigated its effects on systolic blood pressure (SBP) and oxidative stress in rats chronically exposed to nicotine.
  
  
  METHODS
  Male Sprague-Dawley rats (100-120 g) were intraperitoneally injected with 0.8 mg/kg/day nicotine for 21 days, followed by 3 mg/kg nicotine the next day. Rats were subsequently injected intraperitoneally with 0.01, 0.1 and 1 mg/kg 1,8-cineole, or 10 mg/kg nifedipine. SBP was measured using a tail cuff transducer, plasma nitrite concentration was measured colorimetrically, and plasma corticosterone concentration was measured by enzyme immunoassay.
  
  
  RESULTS
  We found that 0.1 mg/kg 1,8-cineole significantly reduced SBP, and that 1.0 mg/kg 1,8-cineole significantly increased plasma nitrite concentrations, compared with rats chronically exposed to nicotine alone. Rats chronically exposed to nicotine showed a significant increase in lipid peroxidation levels, an elevation significantly antagonized by treatment with 0.01 mg/kg and 0.1 mg/kg 1,8-cineole. Chronic exposure to nicotine also significantly increased plasma corticosterone levels, but this effect was not diminished by treatment with 1,8-cineole.
  
  
  CONCLUSIONS
  These results indicate that 1,8-cineole may lower blood pressure, and that this antihypertensive effect may be associated with the regulation of nitric oxide and oxidative stress in rats chronically exposed to nicotine.
authors.affiliation: Department of Basic Nursing Science, School of Nursing, Korea University, Seoul, Republic of Korea.
authors.forename: Hea Kyung
authors.initials: HK
authors.lastname: Moon
authors.forename: Purum
authors.initials: P
authors.lastname: Kang
authors.forename: Hui Su
authors.initials: HS
authors.lastname: Lee
authors.forename: Sun Seek
authors.initials: SS
authors.lastname: Min
authors.forename: Geun Hee
authors.initials: GH
authors.lastname: Seol
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects*; D003511:Cyclohexanols / Q000494:pharmacology / Q000627:therapeutic use*; D000077591:Eucalyptol; D005052:Eucalyptus / Q000737:chemistry; D006973:Hypertension / Q000139:chemically induced / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D039821:Monoterpenes / Q000494:pharmacology / Q000627:therapeutic use*; D009538:Nicotine / Q000009:adverse effects*; D009543:Nifedipine / Q000494:pharmacology / Q000627:therapeutic use; D009569:Nitric Oxide / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D017207:Rats, Sprague-Dawley
chemical_list: D000959:Antihypertensive Agents; D003511:Cyclohexanols; D039821:Monoterpenes; D009573:Nitrites; D010936:Plant Extracts; D009569:Nitric Oxide; D009538:Nicotine; D009543:Nifedipine; D000077591:Eucalyptol
keywords: 1,8-cineole; corticosterone; hypertension; nicotine; nitrite