Grill V, Hillary J, Ho P M, Law F M, MacIsaac R J, MacIsaac I A, Moseley J M, Martin T J
St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia.
Clin Endocrinol (Oxf). 1992 Nov;37(5):405-10. doi: 10.1111/j.1365-2265.1992.tb02350.x.
Parathyroid hormone-related protein (PTHrP), initially discovered as the factor responsible for the syndrome of humoral hypercalcaemia of malignancy, has also been found to be expressed in placenta, in pregnant uterus, in the fetus at many locations, and in the lactating mammary gland. This study sought to establish whether PTHrP reaches the maternal circulation when it is expressed in mammary tissue during lactation or in the maternal reproductive tract during gestation.
Blood samples were collected from 53 subjects: 18 pregnant women in all stages of gestation, 19 lactating mothers and 16 non-lactating post-partum controls.
PTHrP was measured using a specific and validated radioimmunoassay. Parathyroid hormone was measured by two-site immunoradiometric assay. Total calcium was measured by atomic absorption spectrophotometry.
Circulating levels of PTHrP were readily detectable in 12 of 19 nursing mothers (range 2.7-7.8 pmol/l) but in none of the mothers who were bottle feeding. PTHrP was also detected in one of 18 pregnant subjects. Parathyroid hormone concentrations were lower in lactating mothers (2.3 +/- 1.0 pmol/l), than in non-lactating mothers (3.5 +/- 1.2 pmol/l) (P < 0.01).
PTHrP reaches the maternal circulation during lactation in amounts which could produce a systemic effect.
甲状旁腺激素相关蛋白（PTHrP）最初被发现是导致恶性肿瘤体液性高钙血症综合征的因子，后来还发现它在胎盘、妊娠子宫、胎儿的多个部位以及泌乳乳腺中表达。本研究旨在确定当PTHrP在泌乳期乳腺组织或妊娠期母体生殖道中表达时，它是否会进入母体循环。
从53名受试者采集血样：18名处于妊娠各阶段的孕妇、19名哺乳期母亲和16名非哺乳期产后对照者。
使用特异性且经验证的放射免疫测定法测量PTHrP。采用双位点免疫放射测定法测量甲状旁腺激素。通过原子吸收分光光度法测量总钙。
19名哺乳母亲中有12名（范围2.7 - 7.8 pmol/L）可轻易检测到循环中的PTHrP水平，而人工喂养的母亲中均未检测到。18名妊娠受试者中有1名也检测到了PTHrP。哺乳期母亲的甲状旁腺激素浓度（2.3 ± 1.0 pmol/L）低于非哺乳期母亲（3.5 ± 1.2 pmol/L）（P < 0.01）。
PTHrP在泌乳期进入母体循环，其含量可能产生全身效应。
