Basic Science Investigation

Basic Science Investigation

Pregnancy swimming causes short- and long-term neuroprotection against hypoxia–ischemia in very immature rats

  • Pediatric Research volume 82, pages 544553 (2017)
  • doi:10.1038/pr.2017.110
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The first two authors contributed equally to this work.




Hypoxia–ischemia (HI) is a major cause of neurological damage in preterm newborn. Swimming during pregnancy alters the offspring’s brain development. We tested the effects of swimming during pregnancy in the very immature rat brain.


Female Wistar rats (n=12) were assigned to the sedentary (SE, n=6) or the swimming (SW, n=6) group. From gestational day 0 (GD0) to GD21 the rats in the SW group were made to swim for 20 min/day. HI on postnatal day (PND) 3 rats caused sensorimotor and cognitive impairments. Animals were distributed into SE sham (SESH), sedentary HIP3 (SEHI), swimming sham (SWSH), and swimming HIP3 (SWHI) groups. At PND4 and PND5, Na+/K+-ATPase activity and brain-derived neurotrophic factor (BDNF) levels were assessed. During lactation and adulthood, neurological reflexes, sensorimotor, anxiety-related, and cognitive evaluations were made, followed by histological assessment at PND60.


At early stages, swimming caused an increase in hippocampal BDNF levels and in the maintenance of Na+/K+-ATPase function in the SWHI group. The SWHI group showed smaller lesions and the preservation of white matter tracts. SEHI animals showed a delay in reflex maturation, which was reverted in the SWHI group. HIP3 induced spatial memory deficits and hypomyelination in SEHI rats, which was reverted in the SWHI group.


Swimming during pregnancy neuroprotected the brains against HI in very immature neonatal rats.

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Author information


  1. Post-Graduation Program of Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil

    • Eduardo Farias Sanches
    • , Felipe Schmitz
    • , André Rodrigues
    •  & Cassiana Siebert
  2. Department of Biochemistry, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil

    • Andrea Tosta
    • , Cassiana Siebert
    • , Angela Wyse
    •  & Carlos Netto
  3. Post-Graduation Program of Phisiology, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil

    • Luz Elena Durán-Carabali
  4. Post-Graduation Program of Neurosciences, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil

    • Fabrício Nicola


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Competing interests

The authors declare no conflict of interest.

Corresponding author

Correspondence to Eduardo Farias Sanches.

Statement of Financial Support

We are thankful to the following Brazilian agencies for their financial support: CNPq, CAPES, and FAPERGS.


No writing assistance was utilized in the preparation of the manuscript.