Abstract:
:Incubation of sickle cells with cystamine, a thiol reagnet, resulted in the formation of an intracellular S-ethylamine derivative. The rate of the reaction was dependent upon the cystamine concentration, the temperature, and the duration of the incubation. The cystamine-treated cells demonstrated a marked inhibition of sickling under hypoxic conditions, a decrease in their mean corpuscular hemoglobin concentration, and a significant increase in their oxygen affinity. The oxygen affinity of these cells was less dependent on their mean corpuscular hemoglobin concentration than that of untreated sickle cells. The minimum gelling concentration of S-ethylamine doxyhemoglobin S was slightly increased. Cystamine did not affect the intracellular pH nor the 2,3-diphosphoglycerate level. The exact contribution of the interrelated factors in cystamine inhibition of sickling (changes in oxygen affinity, mean corpuscular hemoglobin concentration, and minimum gelling concentration) has yet to be determined.
journal_name
Proc Natl Acad Sci U S Aauthors
Hassan W,Beuzard Y,Rosa Jdoi
10.1073/pnas.73.9.3288keywords:
subject
Has Abstractpub_date
1976-09-01 00:00:00pages
3288-92issue
9eissn
0027-8424issn
1091-6490journal_volume
73pub_type
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