title: Vitamin A Homeostasis in the Diabetic Rat.
abstract: 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.
authors: Division of Life Sciences, The University of Texas at San Antonio, San Antonio, Texas. U.S.A.
authors: Andrew T C
authors: AT
authors: Tsin
authors: Alcon Laboratories, Inc., Fort Worth. Texas, U.S.A.
authors: Brenda W
authors: BW
authors: Griffin
authors: Division of Life Sciences, The University of Texas at San Antonio, San Antonio, Texas. U.S.A.
authors: Nathan L
authors: NL
authors: Mata
authors: Division of Life Sciences, The University of Texas at San Antonio, San Antonio, Texas. U.S.A.
authors: Hing-Sing
authors: HS
authors: Yu
authors: Alcon Laboratories, Inc., Fort Worth. Texas, U.S.A.
authors: Gary W
authors: GW
authors: Williams
authors: Alcon Laboratories, Inc., Fort Worth. Texas, U.S.A.
authors: Julie Y
authors: JY
authors: Cridfr
authors: Alcon Laboratories, Inc., Fort Worth. Texas, U.S.A.
authors: Michael L
authors: ML
authors: Chandler
keywords: diabetes; hyperglycemia; retinyl ester; streptozotocin; vitamin A
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