Vitamin E and selenium regulate balance between beta-adrenergic and muscarinic responses in rat lungs.
The effects of hydrogen peroxide on the beta-adrenergic and muscarinic responses of the rat trachea muscle were studied in vitro, after feeding rats, for 6 weeks, either a diet deficient in vitamin E and selenium or a control diet. In the control situation after incubation with 1 mM hydrogen peroxide for 30 min, a reduction of the maximal response to methacholine of 39% occurred whereas no pD2 shift could be demonstrated. Moreover, no response to isoprenaline after precontraction with 3 x 10(-7) M methacholine was left. In the deficient situation, we found a reduction to 64% of the response to methacholine after incubation with 1 mM hydrogen peroxide. Again isoprenaline became inactive, i.e. no relaxation with isoprenaline was observed after precontraction with 3 x 10(-7) M methacholine. We therefore conclude that vitamin E and selenium protect against oxidative stress in lung tissue and thus regulate the (patho-) physiological balance between adrenergic and muscarinic responses.
Doelman
C J
CJ
Dept of Pharmacochemistry, Faculty of Chemistry, Vrije Universiteit, Amsterdam, The Netherlands.
Kramer
K
K
Timmerman
H
H
Bast
A
A
D000818:Animals; D005979:Glutathione Peroxidase / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008168:Lung / Q000187:drug effects / Q000502:physiology* / Q000503:physiopathology; D008297:Male; D016210:Methacholine Chloride; D008688:Methacholine Compounds / Q000494:pharmacology; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology* / Q000503:physiopathology; D051381:Rats; D011919:Rats, Inbred Strains; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000502:physiology*; D011976:Receptors, Muscarinic / Q000187:drug effects / Q000502:physiology*; D012016:Reference Values; D012643:Selenium / Q000172:deficiency* / Q000494:pharmacology; D014132:Trachea / Q000187:drug effects / Q000502:physiology / Q000503:physiopathology; D014810:Vitamin E / Q000494:pharmacology; D014811:Vitamin E Deficiency / Q000503:physiopathology*
D008688:Methacholine Compounds; D011943:Receptors, Adrenergic, beta; D011976:Receptors, Muscarinic; D016210:Methacholine Chloride; D014810:Vitamin E; D006861:Hydrogen Peroxide; D005979:Glutathione Peroxidase; D012643:Selenium; D007545:Isoproterenol