Blood reservoirs in the splenectomized dog

¹ Department of Physiology, Medical College of Georgia, Augusta, Georgia

Changes in plasma protein concentration, hematocrit, and red cells Cr⁵¹ concentration (count/min per ml blood) were determined following various procedures to acutely alter hemodynamics in an attempt to determine the presence of red cell or plasma reservoirs in splenectomized dogs. The cell reservoir index (percent change in hematocrit minus the percent change in count per minute per milliliter blood) increased significantly following procedures causing increased total peripheral resistance and arterial pressure. These procedures included epinephrine, angiotensin, and norepinephrine infusions as well as cold-pack applications. This was interpreted to be a shift of red cells out of reservoirs. Depressor procedures such as phentolamine followed by epinephrine infusion, isoproterenol, and acetylcholine caused no change in reservoir index. Histamine infusion caused a reduction in cell reservoir index. There was a shift of whole plasma from reservoirs into the active circulation following the infusion of epinephrine into animals previously administered phentolamine. The red cell reservoirs are believed to be generally distributed throughout the organism.

Key Words: red cell volume • red cell reservoirs • plasma reservoir • plasma protein concentration • splenectomized dog

Submitted on July 20, 1964