Abstract
At birth, arterial Po2 (Pao2) in the lamb rises from a fetal value of ca. 25 mm Hg towards the adult value of ca. 100 mm Hg (1), over the first few days (2). One consequence of this rise is that spontaneous carotid chemoreceptor discharge is abolished or greatly reduced for the first 2–3 postnatal days (3). After this period, spontaneous discharge returns (3) and gradually increases (4) as the Po2 stimulus-response curve for these receptors adjusts to the new Pao2. This resetting of chemosensitivity is reflected by a maturation of respiratory chemoreflexes leading to a greater ventilatory response to hypoxia with increasing postnatal age (5,6). However, a failure to reset can result in impaired respiratory control such as seen in rat pups and kittens made chronically hypoxic from birth (7,8). As inadequate respiratory control may contribute towards infant morbidity and mortality, the clinical importance of resetting is clear.
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Kumar, P., Hanson, M.A. (1990). Postnatal Resetting of the Hypoxic Sensitivity of Aortic Chemoreceptors in the Lamb. In: Eyzaguirre, C., Fidone, S.J., Fitzgerald, R.S., Lahiri, S., McDonald, D.M. (eds) Arterial Chemoreception. Springer, New York, NY. https://doi.org/10.1007/978-1-4612-3388-6_38
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DOI: https://doi.org/10.1007/978-1-4612-3388-6_38
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