Tsin Andrew T C, Griffin Brenda W, Mata Nathan L, Yu Hing-Sing, Williams Gary W, Cridfr Julie Y, Chandler Michael L
Division of Life Sciences, The University of Texas at San Antonio, San Antonio, Texas. U.S.A.
Alcon Laboratories, Inc., Fort Worth. Texas, U.S.A.
J Clin Biochem Nutr. 1993;15(1):23-31. doi: 10.3164/jcbn.15.23.
The concentrations of vitamin A (retinol) and retinyl ester in the plasma and liver of normal and diabetic rats were measured by HPLC (high-performance liquid chromatography). Diabetic rats had severe hyperglycemia, induced by a single streptozotocin injection 5 weeks prior to sampling. In the normal rats, plasma retinyl palmitate was very low, and the level was increased 10-fold by diabetes. Detailed time-course studies showed that rats became hyperglycemic within 48 h of streptozotocin injection, yet the plasma retinyl palmitate level was not elevated until some three weeks later. Severe diabetes did not significantly influence plasma retinol: however. free retinol in the liver was elevated within 10 days of initiation of the disease and continued to increase for the duration of the study. These results show that streptozotocin-induced diabetes significantly alters the concentrations of hepatic retinol and plasma retinyl ester. The biochemical mechanism(s) of this altered vitamin A homeostasis in diabetes and its possible relationship to tissue pathogenesis are not known at present.
采用高效液相色谱法（HPLC）测定正常大鼠和糖尿病大鼠血浆及肝脏中维生素A（视黄醇）和视黄酯的浓度。糖尿病大鼠在采样前5周通过单次注射链脲佐菌素诱导产生严重高血糖。在正常大鼠中，血浆棕榈酸视黄酯水平非常低，而糖尿病使其水平升高了10倍。详细的时间进程研究表明，大鼠在注射链脲佐菌素后48小时内出现高血糖，但血浆棕榈酸视黄酯水平直到约三周后才升高。然而，严重糖尿病对血浆视黄醇没有显著影响：疾病开始后10天内肝脏中的游离视黄醇升高，并在研究期间持续增加。这些结果表明，链脲佐菌素诱导的糖尿病显著改变了肝脏视黄醇和血浆视黄酯的浓度。目前尚不清楚糖尿病中这种维生素A稳态改变的生化机制及其与组织发病机制的可能关系。
