Hyperoxia-induced developmental plasticity of the hypoxic ventilatory response in neonatal rats: contributions of glutamate-dependent and PDGF-dependent mechanisms

Bavis, RW; Deangelis, KJ; Horowitz, TC; Reedich, LM; March, RJ

HERO ID

2232214

Reference Type

Journal Article

Year

2014

Language

English

PMID

24284036

HERO ID 2232214
In Press No
Year 2014
Title Hyperoxia-induced developmental plasticity of the hypoxic ventilatory response in neonatal rats: contributions of glutamate-dependent and PDGF-dependent mechanisms
Authors Bavis, RW; Deangelis, KJ; Horowitz, TC; Reedich, LM; March, RJ
Journal Respiratory Physiology and Neurobiology
Volume 191
Page Numbers 84-94
Abstract Rats reared in hyperoxia exhibit a sustained (vs. biphasic) hypoxic ventilatory response (HVR) at an earlier age than untreated, Control rats. Given the similarity between the sustained HVR obtained after chronic exposure to developmental hyperoxia and the mature HVR, it was hypothesized that hyperoxia-induced plasticity and normal maturation share common mechanisms such as enhanced glutamate and nitric oxide signaling and diminished platelet-derived growth factor (PDGF) signaling. Rats reared in 21% O2 (Control) or 60% O2 (Hyperoxia) from birth until 4-5 days of age were studied after intraperitoneal injection of drugs targeting these pathways. Hyperoxia rats receiving saline showed a sustained HVR to 12% O2, but blockade of NMDA glutamate receptors (MK-801) restored the biphasic HVR typical of newborn rats. Blockade of PDGF-β receptors (imatinib) had no effect on the pattern of the HVR in Hyperoxia rats, although it attenuated ventilatory depression during the late phase of the HVR in Control rats. Neither nitric oxide synthase inhibitor used in this study (nNOS inhibitor I and l-NAME) altered the pattern of the HVR in Control or Hyperoxia rats. Drug-induced changes in the biphasic HVR were not correlated with changes in metabolic rate. Collectively, these results suggest that developmental hyperoxia hastens the transition from a biphasic to sustained HVR by upregulating glutamate-dependent mechanisms and downregulating PDGF-dependent mechanisms, similar to the changes underlying normal postnatal maturation of the biphasic HVR.
Doi 10.1016/j.resp.2013.11.006
Pmid 24284036
Wosid WOS:000331028800011
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword Biphasic hypoxic ventilatory response; Hypoxic ventilatory depression; NMDA glutamate receptor; PDGF-beta receptor; Nitric oxide synthase; Heterokairy