Wintour E M, Smith M B, Bell R J, McDougall J G, Cauchi M N
J Endocrinol. 1985 Jan;104(1):165-70. doi: 10.1677/joe.0.1040165.
The switch from gamma (fetal) to beta (adult) globin production was studied by the analysis of globin synthesis in chronically cannulated ovine fetuses and newborn lambs. The gamma/alpha globin synthesis ratio decreased from 0.98 +/- 0.11 (S.D.) (n = 4 samples) at 100-120 days of gestation to 0.15 +/- 0.07 (n = 4) in lambs of 150-156 days post-conception, and the beta/alpha synthesis ratio increased from 0.04 +/- 0.06 (n = 4) to 1.13 +/- 0.21 (n = 4) over the same period. In bilaterally adrenalectomized fetuses, which survived in utero until 151-156 days, the gamma/alpha and beta/alpha synthesis ratios were 0.64 +/- 0.14 (n = 3) and 0.25 +/- 0.07 (n = 3) respectively in the 150- to 156-day period. Bilateral adrenalectomy did not affect the time of onset of beta globin synthesis, but significantly decreased the rate. In one bilaterally adrenalectomized fetus the infusion of increasing concentrations of cortisol restored the rate of beta globin synthesis to normal. Treatment of three intact fetuses with 100 micrograms cortisol/h for 3 weeks, from 100 to 121 days, did not affect the timing or rate of switch from gamma to beta globin synthesis. Thus fetal adrenal secretions, probably cortisol, affected the rate of change of gamma to beta globin synthesis but other factors must have been involved in the initiation of the switch.
通过分析慢性插管绵羊胎儿和新生羔羊的珠蛋白合成，研究了从γ（胎儿型）向β（成人型）珠蛋白产生的转变。γ/α珠蛋白合成比率从妊娠100 - 120天时的0.98±0.11（标准差）（n = 4个样本）降至受孕后150 - 156天羔羊的0.15±0.07（n = 4），而β/α合成比率在同一时期从0.04±0.06（n = 4）增至1.13±0.21（n = 4）。在双侧肾上腺切除的胎儿中，这些胎儿在子宫内存活至151 - 156天，在150 - 156天期间，γ/α和β/α合成比率分别为0.64±0.14（n = 3）和0.25±0.07（n = 3）。双侧肾上腺切除术不影响β珠蛋白合成开始的时间，但显著降低了其速率。在一只双侧肾上腺切除的胎儿中，输注浓度不断增加的皮质醇可使β珠蛋白合成速率恢复正常。在100至121天期间，对三只完整胎儿以100微克皮质醇/小时的剂量治疗3周，并不影响从γ向β珠蛋白合成转变的时间或速率。因此，胎儿肾上腺分泌，可能是皮质醇，影响了γ向β珠蛋白合成的变化速率，但转变的启动肯定还涉及其他因素。
