Global REACH 2018: renal oxygen delivery is maintained during early acclimatization to 4,330 m

Steele, A.R.; Dawkins, T.G.; Stembridge, M.; Meah, V.L.; Gasho, C.; Ainslie, P.N.; Steinback, C.D.; Tymko, M.M.; Simpson, L.L.; Moore, J.P.; Villafuerte, Francisco C.

dc.contributor.author	Steele, A.R.
dc.contributor.author	Tymko, M.M.
dc.contributor.author	Meah, V.L.
dc.contributor.author	Simpson, L.L.
dc.contributor.author	Gasho, C.
dc.contributor.author	Dawkins, T.G.
dc.contributor.author	Villafuerte, Francisco C.
dc.contributor.author	Ainslie, P.N.
dc.contributor.author	Stembridge, M.
dc.contributor.author	Moore, J.P.
dc.contributor.author	Steinback, C.D.
dc.date.accessioned	2020-12-14T16:10:15Z
dc.date.available	2020-12-14T16:10:15Z
dc.date.issued	2020
dc.identifier.uri	https://hdl.handle.net/20.500.12866/8816
dc.description.abstract	Early acclimatization to high altitude is characterized by various respiratory, hematological, and cardiovascular adaptations that serve to restore oxygen delivery to tissue. However, less is understood about renal function and the role of renal oxygen delivery (RDO2) during high altitude acclimatization. We hypothesized that 1) RDO2 would be reduced after 12 h of high altitude exposure (high altitude day 1) but restored to sea level values after 1 wk (high altitude day 7) and 2) RDO2 would be associated with renal reactivity, an index of acid-base compensation at high altitude. Twenty-four healthy lowlander participants were tested at sea level (344 m, Kelowna, BC, Canada) and on day 1 and day 7 at high altitude (4,330 m, Cerro de Pasco, Peru). Cardiac output, renal blood flow, and arterial and venous blood sampling for renin-angiotensin-aldosterone system hormones and NH2-terminal pro-B-type natriuretic peptides were collected at each time point. Renal reactivity was calculated as follows: (Δarterial bicarbonate)/(Δarterial Pco2) between sea level and high altitude day 1 and sea level and high altitude day 7. The main findings were that 1) RDO2 was initially decreased at high altitude compared with sea level (ΔRDO2: -22 ± 17%, P < 0.001) but was restored to sea level values on high altitude day 7 (ΔRDO2: -6 ± 14%, P = 0.36). The observed improvements in RDO2 resulted from both changes in renal blood flow (Δ from high altitude day 1: +12 ± 11%, P = 0.008) and arterial oxygen content (Δ from high altitude day 1: +44.8 ± 17.7%, P = 0.006) and 2) renal reactivity was positively correlated with RDO2 on high altitude day 7 (r = 0.70, P < 0.001) but not high altitude day 1 (r = 0.26, P = 0.29). These findings characterize the temporal responses of renal function during early high altitude acclimatization and the influence of RDO2 in the regulation of acid-base balance.	en_US
dc.language.iso	eng
dc.publisher	American Physiological Society
dc.relation.ispartofseries	American Journal of Physiology. Renal Physiology
dc.rights	info:eu-repo/semantics/restrictedAccess
dc.subject	Acid-base compensation	en_US
dc.subject	Global Research Expedition on Altitude-Related Chronic Health	en_US
dc.subject	High Altitude	en_US
dc.subject	Hypoxia	en_US
dc.subject	Renal Blood Flow	en_US
dc.subject	Renal Oxygen Delivery	en_US
dc.title	Global REACH 2018: renal oxygen delivery is maintained during early acclimatization to 4,330 m	en_US
dc.type	info:eu-repo/semantics/article
dc.identifier.doi	https://doi.org/10.1152/ajprenal.00372.2020
dc.subject.ocde	https://purl.org/pe-repo/ocde/ford#3.01.08
dc.subject.ocde	https://purl.org/pe-repo/ocde/ford#3.02.20
dc.relation.issn	1522-1466