De Simone J, Mueller A L
Blood. 1979 Jan;53(1):19-27.
Fetal hemoglobin (HbF) and adult hemoglobin (HbA) synthesis was studied in fetal baboons, Papio cynocephalus, to determine the normal pattern of hemoglobin production during fetal development. Fetuses ranging from 53 to 180 days gestation (term gestation 184 days) were used. Erythroid cells were incubated with 3H-L-leucine, and the rates of globin chain synthesis and the distribution of radioactivity into hemoglobin intermediates and completed hemoglobin molecules were determined. Gamma chain synthesis accounted for approximately 97% of the total nonalpha chain synthesis up to 140 days gestation; beta chain synthesis accounted for the remainder. After 140 days gestation, approximately equal quantities of gamma and beta chain were synthesized in the bone marrow. Prior to 140 days gestation, total alpha chain synthesis was 30% greater than total non-alpha chain synthesis, while there was balanced chain synthesis after 140 days gestation. During the period of excess alpha chain synthesis, fetal erythrocytes contained a large pool of alpha-hemoglobin (alpha chain with heme attached) molecules uncombined with beta or gamma chains. In view of the possibility that alpha chains may have a lower affinity for gamma chains than beta chains, excess alpha chain synthesis may be required to maintain low levels of free gamma chains.
为了确定胎儿发育过程中血红蛋白产生的正常模式，对胎生狒狒（豚尾狒狒）的胎儿血红蛋白（HbF）和成人血红蛋白（HbA）合成进行了研究。使用了妊娠53至180天（足月妊娠184天）的胎儿。将红系细胞与³H-L-亮氨酸一起孵育，并测定珠蛋白链合成速率以及放射性在血红蛋白中间体和完整血红蛋白分子中的分布。在妊娠140天之前，γ链合成约占非α链总合成量的97%；其余为β链合成。妊娠140天后，骨髓中合成的γ链和β链数量大致相等。在妊娠140天之前，α链总合成量比非α链总合成量高30%，而妊娠140天后链合成是平衡的。在α链合成过量的时期，胎儿红细胞含有大量未与β或γ链结合的α-血红蛋白（附着有血红素的α链）分子。鉴于α链对γ链的亲和力可能低于β链，可能需要过量的α链合成来维持游离γ链的低水平。
