Abstract
Neonatal hypoxia-ischemia (HI) affects 60% of low birth weight infants and up to 40% of preterm births. Cell death and brain injury after HI have been shown to cause long-lasting neurological deficits. Two motor coordination tests on rats that had been exposed to HI on postnatal day 7 (P7) showed that HI in the P7 rat is associated with significant motor coordination impairment. These results call attention to the risks associated with perinatal ischemia and the need for proper treatment to reverse HI-induced deleterious effects.
Keywords: Motor coordination, Balance, Inclined plane, Rat, Hypoxia
Materials and Reagents
Equipment
Note: Both rod and incline wire mesh are self-made from supplies bought at hardware store.
Procedure
Motor coordination is assessed 21 days (P28) after HI insult [see Vannucci et al. (1999) for a description of HI protocol] as modified by us (Ferrari et al., 2010). Briefly, pregnant Wistar rat dams at gestational age E17 are housed in 12 h light-dark cycle with ad libitum access to food and water. The day of birth is postnatal day 0 (P0) and on P1 the litters are culled to 10 pups per dam and randomly mixed amongst dams to yield 20 pups per experiment. On day P7 all pups are removed from dams, weighed, sexed and randomly assigned to a group: sham- or HI-treated. They are then anesthetized and the left carotid artery isolated and permanently ligated. Sham pups are only anesthetized, an incision is made, immediately sutured and the wound cleaned without any further manipulation. Upon recovery, pups are returned to dams for 90 min and then they are removed and exposed to 8% oxygen for 90 min at which point they are returned to dams.
Representative data
Figure 1. Bar holding test Figure 2. Wire mesh ascending test Figure 3. HI impairs motor coordination (Ferrari et al., 2010)
Notes
Acknowledgments
This work was supported by Department of Defense, NIEHS and NICHD.
References
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