Upregulation of alveolar liquid clearance after fluid resuscitation for hemorrhagic shock in rats

Am J Physiol. 1997 Aug;273(2 Pt 1):L305-14. doi: 10.1152/ajplung.1997.273.2.L305.


The primary objective of this study was to test the hypothesis that a catecholamine-dependent mechanism would upregulate alveolar liquid clearance after fluid resuscitation from 15 min of hemorrhagic shock. Anesthetized rats were hemorrhaged to a mean arterial pressure of 35 mmHg for 15 min and were resuscitated with a 4% albumin solution. Alveolar liquid clearance was measured 5 h later by the concentration of protein in the distal airspaces over 1 h after instillation of a 5% albumin solution into one lung. Hemorrhaged rats developed a severe metabolic acidosis that was associated with a significant rise-in plasma epinephrine levels throughout the study. There was a 60% increase in alveolar liquid clearance in hemorrhaged and resuscitated rats compared with control rats. Amiloride (10(-4) or 10(-6) M), propranolol (10(-4) M), or bilateral adrenalectomy inhibited the increase in alveolar liquid clearance. This effect was reproduced by the intravenous administration of epinephrine in adrenalectomized and hemorrhaged rats. Thus these data provide evidence for a catecholamine-dependent regulation of sodium transport that protects the airspaces against flooding several hours after fluid resuscitation from hemorrhagic shock.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adrenalectomy
  • Amiloride / administration & dosage
  • Amiloride / pharmacology
  • Animals
  • Epinephrine / administration & dosage
  • Epinephrine / pharmacology
  • Fluid Therapy*
  • Infusions, Intravenous
  • Male
  • Propranolol / administration & dosage
  • Propranolol / pharmacology
  • Pulmonary Alveoli / metabolism*
  • Rats
  • Rats, Sprague-Dawley
  • Resuscitation*
  • Shock, Hemorrhagic / therapy*


  • Amiloride
  • Propranolol
  • Epinephrine