Article Text

other Versions

PDF
Exercise pretraining protects against heatstroke-induced cerebral ischemia in rats
  1. Yu-Wen Chen (cywhwok{at}yahoo.com.tw)
  1. Department of Medical Research, Chi Mei Medical Center, Taiwan
    1. Sheng-Hsien Chen
    1. Department of Medical Research, Chi Mei Medical Center, Taiwan
      1. Willy Chou
      1. Department of Rehabilitation Medicine, Chi Mei Medical Center, Taiwan
        1. Yi-Ming Lo
        1. Department of Rehabilitation Medicine, Chi Mei Medical Center, Taiwan
          1. Ching-Hsia Hung (chhung{at}mail.ncku.edu.tw)
          1. Department of Physical Therapy, National Cheng Kung University, Taiwan
            1. Mao-Tsun Lin
            1. Department of Medical Research, Chi Mei Medical Center, Taiwan

              Abstract

              Background: In the rat brain, heatstroke-induced damage to cerebral neurons is attenuated through heat-shock induced overexpression of heat shock protein 72 (HSP72).

              Objective: To ascertain whether progressive exercise preconditioning induces HSP72 expression in the rat brain and prevents heatstroke-induced cerebral ischemia and injury.

              Methods: Male Wistar rats were randomly assigned to either a sedentary group or an exercise group. Exercise group animals progressively ran on a treadmill 5 days/week, 30-60 min/day at an intensity of 20-30 m/min for 3 weeks. The effects of heatstroke on mean arterial pressure (MAP), cerebral blood flow (CBF), brain ischemia markers (glutamate, lactate/pyruvate ratio and nitric oxide), cerebral injury marker (glycerol), and brain neuronal damage score in the preconditioned animals were compared with unexercised controls. Heatstroke was induced by exposing the urethane-anesthetized animals to a temperature of 43 ˚C for 55 min which caused and the body temperature of the animals to reach 42 ˚C.

              Results: Three weeks of progressive exercise pretreatment induced HSP72 preconditioning in the brain and conferred significant protection against heatstroke-induced hyperthermia, arterial hypotension, cerebral ischemia and neuronal damage; it also prolonged animal survival.

              Conclusions: Exercise for 3 weeks can improve heat tolerance as well as attenuate heatstroke-induced cerebral ischemia in rats. The maintenance of appropriate levels of MAP and CBF in the rat brain may be related to the overexpression of HSP72.

              Statistics from Altmetric.com

              Request permissions

              If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.