Berkowitz B A, Head R, Joh T, Hempstead J
J Pharmacol Exp Ther. 1980 Apr;213(1):18-23.
Dopamine-beta-hydroxylase (DBH) activity is increased at least 5-fold in the serum of rats with experimental diabetes produced by Streptozotocin or Alloxan. The increased DBH activity persisted for 7 months. Dialysis did not reduce the elevated activity. Based on a large increase in the maximal velocity of the enzyme reaction and immunoprecipitation studies, there appears to be increased amounts of DBH in the serum of diabetic rats. Thyroxin and triiodothyronine concentrations were reduced in diabetic serum but replacement doses of these hormones did not correct the high DBH activity. In contrast, adrenalectomy or insulin administration prevented the diabetes and elevations of circulating DBH. Circulating norepinephrine levels in arterial and venous blood were measured at 4 and 16 weeks after the onset of diabetes and elevated only in venous blood at the early time interval. In summary, circulating DBH levels were increased in experimental diabetes but did not correlate with circulating norepinephrine levels. Further studes are required to differentiate between the possibilities of increased sympathetic nervous system activity and altered DBH turnover in experimental diabetes.
用链脲佐菌素或四氧嘧啶诱导产生实验性糖尿病的大鼠血清中，多巴胺-β-羟化酶（DBH）活性至少升高5倍。DBH活性升高持续了7个月。透析并不能降低升高的活性。基于酶反应最大速度的大幅增加和免疫沉淀研究，糖尿病大鼠血清中DBH的量似乎有所增加。糖尿病血清中甲状腺素和三碘甲状腺原氨酸浓度降低，但这些激素的替代剂量并不能纠正高DBH活性。相反，肾上腺切除术或胰岛素给药可预防糖尿病及循环中DBH的升高。在糖尿病发病后4周和16周测量动脉血和静脉血中的循环去甲肾上腺素水平，仅在早期时间间隔静脉血中升高。总之，实验性糖尿病中循环DBH水平升高，但与循环去甲肾上腺素水平无关。需要进一步研究以区分实验性糖尿病中交感神经系统活性增加和DBH周转改变的可能性。
