English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

This study investigated trans-cerebral internal jugular venous-arterial bicarbonate ([HCO 3  - ]) and carbon dioxide tension (PCO 2 ) exchange utilizing two separate interventions to induce acidosis: 1) acute respiratory acidosis via elevations in arterial PCO 2 (PaCO 2 ) (n = 39); and 2) metabolic acidosis via incremental cycling exercise to exhaustion (n = 24). During respiratory acidosis, arterial [HCO 3  - ] increased by 0.15 ± 0.05 mmol ⋅ l -1 per mmHg elevation in PaCO 2 across a wide physiological range (35 to 60 mmHg PaCO 2 ; P &lt; 0.001). The narrowing of the venous-arterial [HCO 3  - ] and PCO 2 differences with respiratory acidosis were both related to the hypercapnia-induced elevations in cerebral blood flow (CBF) (both P &lt; 0.001; subset n = 27); thus, trans-cerebral [HCO 3  - ] exchange (CBF × venous-arterial [HCO 3  - ] difference) was reduced indicating a shift from net release toward net uptake of [HCO 3  - ] (P = 0.004). Arterial [HCO 3  - ] was reduced by -0.48 ± 0.15 mmol ⋅ l -1 per nmol ⋅ l -1 increase in arterial [H + ] with exercise-induced acidosis (P &lt; 0.001). There was no relationship between the venous-arterial [HCO 3  - ] difference and arterial [H + ] with exercise-induced acidosis or CBF; therefore, trans-cerebral [HCO 3  - ] exchange was unaltered throughout exercise when indexed against arterial [H + ] or pH (P = 0.933 and P = 0.896, respectively). These results indicate that increases and decreases in systemic [HCO 3  - ] - during acute respiratory/exercise-induced metabolic acidosis, respectively - differentially affect cerebrovascular acid-base balance (via trans-cerebral [HCO 3  - ] exchange).

journal of cerebral blood flow and metabolism

Trans-cerebral HCO3− and PCO2 exchange during acute respiratory acidosis and exercise-induced metabolic acidosis in humans