生长介素对肢端肥大症患者垂体瘤生长激素分泌影响的体外研究

EFFECT OF INSULIN-LIKE GROWTH FACTOR-1 ON GROWTH HORMONE SECRETION OF ACROMEGALIC PITUITARY TUMORS IN VITRO

作者在8例肢端肥大症体外培养的垂体GH瘤细胞上探讨IGF-1对GH分泌的反馈调节作用。10^(-7)mol IGF-1使3例垂体GH瘤细胞GH基础分泌抑制到对照的44.6％～52.4％(P<0.05),1例GH分泌增加134.9％(P<0.05),4例GH基础分泌没有明显改变,表明体外培养的垂体GH瘤有一半以上对IGF-1 3小的·的急性作用失去正常的GH分泌抑制反应。3例对IGF-1失去GH分泌抑制反应的垂体GH瘤细胞同时伴有GH对GHRH_(1-44)及(或)生长抑素激动剂SMS_(201-995)反应消失,提示部分垂体GH瘤细胞的IGF-1和某些下丘脑激素受体或受体后有异常。

The feedback regulation of IGF-1 on GH secretion from acromegalic pituitary tumors in cell culture was studied in 8 cases. 10-7mol/LIGT-1 significantly inhibited GH basal secretion to 44.6~52.4% of the control in 3 tumors(P<0.05), increased GH secretion to 134.9% of the control in 1 tumor (P<0.05) and was ineffective in 4 tumors. The results demonstrated that the suppression of GH secretion by IGF-1 in normal pituitary was disappeared in mere than 50% of the pituitary GH-secreting tumors. The responses of GH secretion to GHRH1-44 and/or SMS201-995 were lost also in 3 pituitary GH-secreting tumors which had no response to IGF-1. It is suggested that the receptors of IGF-1 and some hypothalamic hormone are abnormal in some acromegalic pituitary tumors.