Acute Elevations in Apnea‐Induced Spleen Contraction Provoked by Thermoneutral Head Out Water Immersion

Abstract

The spleen serves as a repository of erythrocytes that can be jettisoned into circulation following sympathetic stimulation, such as hypoxia or apnea. Evidence supports that there may be a functional benefit to spleen contraction during breath‐hold diving, likely by increasing oxygen carrying and pH buffering capacities. However, the magnitude of apnea‐induced spleen contraction during immersion, and the corresponding hematological changes, have not been quantified. We have recently identified that spleen volume increases after 30 min of thermoneutral head out water immersion (HOWI), likely due to initial hydrostatic pressure‐induced increases in central blood volume, and remains elevated through 135 min, despite immersion‐induced diuresis. Whether these HOWI‐induced changes in spleen volume modify the magnitude of apnea‐induced spleen contraction is unknown. Cross‐sectional observations indicate that there is a positive relation between baseline spleen volume and the magnitude of apnea‐induced spleen contraction.

Document Details

Document Type
Pub Defense Publication
Publication Date
May 01, 2022
Source ID
10.1096/fasebj.2022.36.s1.r5110

Entities

People

  • Blair D Johnson
  • Erica Tourula
  • Hayden W Hess
  • Jason M. Keeler
  • Joel T. Greenshields
  • Payton M. Kerr
  • Richara Logan
  • Robert F. Chapman
  • Tyler B. Baker
  • Zachary J Schlader

Organizations

  • Indiana University
  • Office of Naval Research

Tags

Readers

  • Cardiovascular Physiology
  • Exercise and Sports Science.
  • Theoretical Analysis.