Abstract
In neonatal rats, neutrophils do not accumulate in ischemic brain parenchyma to the extent that they do in adult rodents. They are also confined to the intravascular compartment during the first few hours of recovery. However, neonatal rats rendered neutropenic have less brain swelling after a hypoxic-ischemic (HI) insult. In this study, we used the Rice-Vannucci model of HI brain injury in 7-d-old rats, and we depleted neutrophils before injury in one group and 4-8 h after injury in another group to determine 1) whether neutrophils contribute to cerebral atrophy, 2) whether neutropenia induced within 8 h after recovery from HI is neuroprotective, and 3) whether neutropenia preserved energy metabolites during the HI insult. Brain energy metabolites were measured at 0 h and 6 h of recovery. Brain atrophy was measured morphometrically on brain slices at 2 wk of recovery. In 67 rats, we found that neutropenia induced before the HI insult, but not after HI, reduced brain swelling at 42 h of recovery by about 75% (p < 0.001). In another 60 rats, we found that cerebral atrophy was reduced by 61% provided that neutropenia was induced before HI (p < 0.05). Total adenine nucleotides were better preserved in the neutropenic rats at the end of the HI insult (0 h recovery); p < 0.05. We conclude that neutrophils do contribute to vascular dysfunction either during the HI insult or early hours (<4-8 h) of recovery. Antineutrophil strategies initiated after this time are unlikely to be protective in the neonatal rat.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.