Hwang D L, Lev-Ran A
Department of Diabetes, City of Hope National Medical Center Duarte, California.
Life Sci. 1990;47(8):679-85. doi: 10.1016/0024-3205(90)90622-x.
Levels of epidermal growth factor (EGF) in serum were significantly decreased in streptozotocin (STZ)-diabetic mice (446 +/- 168 pg/ml after 1 week and 423 +/- 52 after 4 weeks vs 766 +/- 162 pg/ml in controls, P.002 and less than .001. respectively) and in genetically diabetic ob/ob mice (455 +/- 285 vs 962 +/- 453 pg/ml in nondiabetic ob/+ controls, P.043). The urinary excretion of EGF was significantly increased in STZ mice (104 +/- 53 vs 51 +/- 23 ng/h, P.013) but unchanged in ob/ob mice (33 +/- 9 vs 45 +/- 16 ng/h, P.134). However, when expressed per mg creatinine it was decreased in both cases: in STZ mice to 680 +/- 250 ng/mg at 1 week and 684 +/- 211 at 4 weeks vs 1250 +/- 303 ng/mg in controls (P less than .01); and in the ob/ob mice to 552 +/- 117 vs 1237 +/- 300 ng/mg in ob/+ controls (P less than .01). EGF content of the submandibular glands of STZ mice remained unchanged at 1 week (13.1 +/- 2.9 vs 11.0 +/- 1.8 micrograms/mg protein, P.170) but dropped by 4 weeks (4.7 +/- 1.2 micrograms/mg, P less than .001); in the ob/ob mice it was less than 20% that of controls (2.1 +/- 0.8 vs 12.2 +/- 3.6 micrograms/mg protein). In kidneys, the EGF content was not altered in either ob/ob (524 +/- 50 vs 571 +/- 33 pg/mg protein) or STZ mice (652 +/- 183 vs 665 +/- 80 pg/mg). The preproEGF mRNA level in STZ-treated mice was reduced after 4 weeks in submandibular glands but not in kidneys. The results show that diabetes affects EGF production, utilization and/or excretion in mice and that kidneys are spared from suppression of EGF synthesis that is pronounced in the submandibular glands.
链脲佐菌素（STZ）诱导的糖尿病小鼠血清中的表皮生长因子（EGF）水平显著降低（1周后为446±168 pg/ml，4周后为423±52 pg/ml，而对照组为766±162 pg/ml，P<0.002和P<0.001），遗传性糖尿病ob/ob小鼠也是如此（455±285 vs非糖尿病ob/+对照组的962±453 pg/ml，P<0.043）。STZ小鼠的EGF尿排泄量显著增加（104±53 vs 51±23 ng/h，P<0.013），但ob/ob小鼠无变化（33±9 vs 45±16 ng/h，P>0.134）。然而，以每毫克肌酐表示时，两种情况均降低：STZ小鼠在1周时降至680±250 ng/mg，4周时降至684±211 ng/mg，而对照组为1250±303 ng/mg（P<0.01）；ob/ob小鼠降至552±117 ng/mg，而ob/+对照组为1237±300 ng/mg（P<0.01）。STZ小鼠下颌下腺的EGF含量在1周时保持不变（13.1±2.9 vs 11.0±1.8微克/毫克蛋白，P>0.170），但在4周时下降（4.7±1.2微克/毫克，P<0.001）；ob/ob小鼠的EGF含量不到对照组的20%（2.1±0.8 vs 12.2±3.6微克/毫克蛋白）。在肾脏中，ob/ob小鼠（524±50 vs 571±33 pg/毫克蛋白）和STZ小鼠（652±183 vs 665±80 pg/毫克）的EGF含量均未改变。STZ处理的小鼠在4周后下颌下腺中的前proEGF mRNA水平降低，但肾脏中未降低。结果表明，糖尿病会影响小鼠体内EGF的产生、利用和/或排泄，并且肾脏未受到EGF合成抑制的影响，而下颌下腺中这种抑制作用较为明显。
