大鼠体内内源性及放射性碘化甲状腺球蛋白的代谢清除率

Metabolic clearance of endogenous and radioiodinated thyroglobulin in rats.

作者信息

Izumi M, Larsen P R

出版信息

Endocrinology. 1978 Jul;103(1):96-100. doi: 10.1210/endo-103-1-96.

Abstract

The basal concentration and metabolic clearance of radiolabeled and endogenous thyroglobulin (Tg) were measured in normal male rats. Serum Tg concentrations (by RIA) in Sprague-Dawley adult males ranged from 70-680 ng/ml (mean +/- SD, 218 +/- 177). In male Fisher rats, basal serum Tg concentrations were 32-263 ng/ml. The fractional disappearance rate of endogenously radioiodinated rat Tg and of endogenous rat Tg after thyroidectomy were both about 8%/h. The MCR of endogenously labeled Tg was 2.4 +/- 1.1 ml/100 g/h. Using this clearance and the mean serum Tg concentration in these rats, a daily thyroidal release rate of about 201 microgram Tg/100 g BW would be required to provide the T4 metabolized daily by the rat, the Tg released into the circulation comprises about 7% of the total rat Tg produced in a 24-h period.

摘要

在正常雄性大鼠中测量了放射性标记的和内源性甲状腺球蛋白（Tg）的基础浓度和代谢清除率。成年雄性Sprague-Dawley大鼠的血清Tg浓度（通过放射免疫分析）范围为70 - 680 ng/ml（平均值±标准差，218±177）。在雄性Fisher大鼠中，基础血清Tg浓度为32 - 263 ng/ml。内源性放射性碘化大鼠Tg和甲状腺切除术后内源性大鼠Tg的分数消失率均约为8%/小时。内源性标记Tg的代谢清除率为2.4±1.1 ml/100 g/小时。利用该清除率和这些大鼠的平均血清Tg浓度，为提供大鼠每日代谢的T4，每日甲状腺释放率约为201微克Tg/100 g体重，释放到循环中的Tg约占大鼠在24小时内产生的总Tg的7%。