Glutamatergic Receptors Modulate Normoxic but Not Hypoxic Ventilation and Metabolism in Naked Mole Rats
| Autor: | Yvonne A. Dzal, Allison Seow, Lisa G. Borecky, Danielle Chung, Sharn K. G. Gill, William K. Milsom, Matthew E. Pamenter |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
medicine.medical_specialty
Respiratory rate Physiology Hypoxic ventilatory response hypoxic metabolic response Acclimatization lcsh:Physiology 03 medical and health sciences Glutamatergic 0302 clinical medicine Physiology (medical) Internal medicine medicine AMPA receptor Tidal volume 030304 developmental biology Original Research 0303 health sciences lcsh:QP1-981 Chemistry hypoxic ventilatory response Hypoxia (medical) NMDA receptor Endocrinology Control of respiration medicine.symptom 030217 neurology & neurosurgery ventilatory acclimatization to hypoxia |
| Zdroj: | Frontiers in Physiology Frontiers in Physiology, Vol 10 (2019) |
| ISSN: | 1664-042X |
| Popis: | Naked mole rats (Heterocephalus glaber) are among the most hypoxia-tolerant mammals, but their physiological responses to acute and chronic sustained hypoxia (CSH), and the molecular underpinnings of these responses, are poorly understood. In the present study we evaluated the acute hypoxic ventilatory response and the occurrence of ventilatory acclimatization to hypoxia following CSH exposure (8-10 days in 8% O2) of naked mole rats. We also investigated the role of excitatory glutamatergic signaling in the control of ventilation and metabolism in these conditions. Animals acclimated to normoxia (control) or CSH and then exposed to acute hypoxia (7% O2 for 1 h) exhibited elevated tidal volume (VT), but decreased breathing frequency (fR). As a result, total ventilation ( V . E) remained unchanged. Conversely, VT was lower in CSH animals relative to controls, suggesting that there is ventilatory plasticity following acclimatization to chronic hypoxia. Both control and CSH-acclimated naked mole rats exhibited similar 60-65% decreases in O2 consumption rate during acute hypoxia, and as a result their air convection requirement (ACR) increased ∼2.4 to 3-fold. Glutamatergic receptor inhibition decreased fR, V . E, and the rate of O2 consumption in normoxia but did not alter these ventilatory or metabolic responses to acute hypoxia in either the control or CSH groups. Taken together, these findings indicate that ventilatory acclimatization to hypoxia is atypical in naked mole rats, and glutamatergic signaling is not involved in their hypoxic ventilatory or metabolic responses to acute or chronic hypoxia. |
| Databáze: | OpenAIRE |
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