PMID: 10430Nov 1, 1976

Effect of sodium para-aminosalicylate on oxygen affinity in normal, sickle and fetal human blood

The Journal of Pharmacology and Experimental Therapeutics
L H LaasbergM B Laver


Sodium para-aminosalicylate (sodium salt of 2-hydroxy-4-aminobenzoic acid, Na-PAS) lowers the oxygen affinity of normal adult human placental, heterozygous and homozygous sickle cell anemic whole blood at 37 degrees C. The reduction of oxygen affinity is related to the type of hemoglobin in the blood. The mean P50 +/- S.E. at pH 7.40 for normal, placental, heterozygoud and homozygous sickle cell anemic blood in 26.2 +/- 0.1, 20.8 +/- 0.3, 26.8 +/- 0.3 and 31.0 +/- 0.5 mm Hg; in the presence of 5.7 mmol of Na-PAS per liter of blood the P50 values are increased to 28.0 +/- 0.3, 22.9 +/- 0.8, 30.5 +/- 0.6 and 33.9 +/- 0.3 mm Hg, respectively. The Bohr effect in normal and placental blood at this Na-PAS concentration is essentially unchanged: in heterozygous and homozygous sickle cell anemic blood, the Bohr factor (deta log P50/deta pH) is reduced from -0.48 +/- 0.02 to -0.41 +/- 0.01 and from -0.53 +/- 0.03 to -0.48 +/- 0.01. The Hill constants (n) of normal and placental blood are not affected by Na-PAS. In homozygous and heterozygous sickle blood, high concentrations of Na-PAS (22.9 mmol/l) decrease the Hill constant from 2.55 to 2.35 and from 2.56 to 2.28, respectively. Na-PAS is more firmly bound to red blood cells than to pla...Continue Reading

Related Concepts

Aminosalicylic Acids
Anemia, Sickle Cell
Physical Dialysis
Diphosphoglyceric Acids
Abnormal Red Blood Cell
Umbilical Cord Blood
Genetic Carriers
Hydrogen-Ion Concentration

Related Feeds

Blood And Marrow Transplantation

The use of hematopoietic stem cell transplantation or blood and marrow transplantation (bmt) is on the increase worldwide. BMT is used to replace damaged or destroyed bone marrow with healthy bone marrow stem cells. Here is the latest research on bone and marrow transplantation.


Anemia develops when your blood lacks enough healthy red blood cells. Anemia of inflammation (AI, also called anemia of chronic disease) is a common, typically normocytic, normochromic anemia that is caused by an underlying inflammatory disease. Here is the latest research on anemia.