Dietary soy may not confound acute experimental stroke infarct volume outcomes in ovariectomized female rats

Kamm Prongay, Anne Lewis, Patricia D. Hurn, Stephanie J. Murphy

    Research output: Contribution to journalArticle

    8 Citations (Scopus)

    Abstract

    Oestrogen administration can alter experimental stroke outcomes. Soy as a source of phytoestrogens may therefore modulate responses in 'oestrogen-sensitive' stroke models, thus potentially confounding results.We evaluated the effects of dietary soy on acute infarct volumes in a pilot study using a rat focal stroke model. We hypothesized that ovariectomized (OVX) rats fed a soy-rich diet would have smaller acute infarct volumes than rats fed a soy-free diet. OVX rats were randomly assigned to a soy-free (n = 6) or a soy-rich (n = 6) diet for four weeks and weighed weekly. Following the dietary trial, rats underwent 2 h of middle cerebral artery occlusion (MCAO). Mean arterial blood pressure, rectal and temporalis muscle temperatures, arterial blood gases and blood glucose were recorded peri-ischaemia. Rats were euthanized 22 h following 2 h of MCAO. Brains were stained with 2,3,5-triphenyl tetrazolium chloride for acute infarct volume analysis. Uterine weight and histology were also evaluated as additional internal oestrogen-sensitive controls. Rats on the soy-free diet had greater gains in body weight (259±6% baseline body weight) than rats on the soy-rich diet (238±4% baseline body weight). No differences were seen in uterine weight and histology, peri-ischaemic physiological parameters and infarct volumes between the treatment groups. The results of this pilot study suggest that the dietary soy level tested may not alter acute infarct volumes in ischaemic female rat brain. More studies addressing the potential confounding effects of dietary soy in 'oestrogen-sensitive' stroke models are needed if investigators are to make informed choices regarding diets used in experimental stroke research.

    Original languageEnglish (US)
    Pages (from-to)238-246
    Number of pages9
    JournalLaboratory Animals
    Volume44
    Issue number3
    DOIs
    StatePublished - 2010

    Fingerprint

    infarction
    stroke
    Stroke Volume
    Stroke
    rats
    Diet
    estrogens
    Estrogens
    diet
    Middle Cerebral Artery Infarction
    Body Weight
    arteries
    histology
    body weight
    Histology
    Arterial Pressure
    brain
    Weights and Measures
    Phytoestrogens
    plant estrogens

    Keywords

    • Cerebral ischaemia
    • Phytoestrogen
    • Soy
    • Stroke

    ASJC Scopus subject areas

    • Animal Science and Zoology
    • veterinary(all)
    • Medicine(all)

    Cite this

    Dietary soy may not confound acute experimental stroke infarct volume outcomes in ovariectomized female rats. / Prongay, Kamm; Lewis, Anne; Hurn, Patricia D.; Murphy, Stephanie J.

    In: Laboratory Animals, Vol. 44, No. 3, 2010, p. 238-246.

    Research output: Contribution to journalArticle

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