title: Aging impairs the protective effect of magnesium supplementation on hypertension in spontaneously hypertensive rats.
abstract: Preeclampsia is a hypertensive disorder that is unique to pregnancy. Magnesium (Mg2+) supplementation is a potential new therapy to ameliorate development of hypertension. The aim of this work was to compare the effects of Mg2+ supplementation on systolic blood pressure (SBP) in young and aged rats. Spontaneously hypertensive rats (SHR) were divided into young (6-week-old male, n = 10) and old (16-week-old male, n = 10) groups. Each group of rats comprised two subgroups made of a control subgroup fed with normal rat chow (0.2% Mg2+, n = 5) and a high Mg2+ subgroup nourished with a Mg2+ rich diet (0.8% Mg2+, n = 5). Age-matched Wistar-Kyoto rats (WKY) were also allocated into two groups. SBP was assessed weekly for 12 weeks indirectly by the tail-cuff method. SBP increased progressively in SHR-young rats after 7 weeks. This increase was greater in the control subgroup compared to high Mg2+ subgroup at 7 weeks (p < 0.05). No difference in the SBP was registered between old SHR subgroups. Mg2+ supplementation does not exert antihypertensive effects in the WKY rats. In conclusion, Mg2+ supplementation may provide beneficial effect in the developmental phase of hypertension but not in established hypertension.
authors.affiliation: Department of Obstetrics and Gynecology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara, 634-8522, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Sado
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Oi
authors.forename: Mariko
authors.initials: M
authors.lastname: Sakata
authors.forename: Shozo
authors.initials: S
authors.lastname: Yoshida
authors.forename: Ryuji
authors.initials: R
authors.lastname: Kawaguchi
authors.forename: Seiji
authors.initials: S
authors.lastname: Kanayama
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Shigetomi
authors.forename: Shoji
authors.initials: S
authors.lastname: Haruta
authors.forename: Yoriko
authors.initials: Y
authors.lastname: Tsuji
authors.forename: Sachiyo
authors.initials: S
authors.lastname: Ueda
authors.forename: Takashi
authors.initials: T
authors.lastname: Kitanaka
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Yamada
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kobayashi
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D019587:Dietary Supplements; D006973:Hypertension / Q000188:drug therapy* / Q000503:physiopathology; D008274:Magnesium / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D013997:Time Factors
chemical_list: D008274:Magnesium