Tissue uptake and distribution of retinol from circulatory vitamin A transport complex was studied in order to determine the origin of the increased serum retinol in rats with short-term acute renal failure. In rats with acute renal failure, serum retinol increased 37-70% within 2 h after surgery. After an injection of donor plasma containing 1.8 muCi of [3H]retinol in retinol transport complex...

Nutritional status may be an important factor in the prognosis of morbidity and mortality. We assessed the nutritional status of individuals seropositive for human immunodeficiency virus (HIV) (as confirmed by Western blot) and of patients with AIDS, by determining the concentration in serum of total protein, albumin, prealbumin (transthyretin), and retinol-binding protein. HIV-seropositive ind...

Adipose tissue is an important storage depot for retinol, but there are no data regarding retinol mobilization from adipose stores. To address this, dibutyryl cAMP was provided to murine BFC-1beta adipocytes and its effects on retinol efflux assessed. High performance liquid chromatography analysis of retinol and retinyl esters in adipocytes and media indicated that cAMP stimulated, in a time- ...

A new procedure for the determination of retinol (vitamin A alcohol) in blood has been devised. It consists of direct measurement of the fluorescence of retinol (excitation 335 nm.; emission 458 nm.) in diluted serum, and is considerably more rapid than any previous method. Such measurements are feasible because the intensity of fluorescence of retinol bound to its transport protein (retinol-bi...

Bovine and human retinol-retinol-binding protein (RBP) were iodinated to high specific activity. At least 34% of the iodinated material was native and retained its retinol chromophore as judged by its characteristic ability to bind to plasma prealbumin. Bovine and human retinol-125I-RBP were found to bind specifically to intact isolated pigment epithelium cells from bovine eyes. The specific bi...

Hyporetinemia is observed in several pathological conditions including a primary deficiency of vitamin A and has also been reported to accompany inflammatory diseases. Experimental magnesium (Mg) deficiency in rodents is accompanied by an inflammatory syndrome. The present study was designed to determine whether the acute phase response in Mg-deficient rats can modify vitamin A status. Clinical...

The high-speed supernatant fraction of rat liver, lung, kidney, testis, and intestinal mucosa contains a component capable of binding [(3)H]retinol in vitro when binding is analyzed by sucrose density gradient centrifugation or gel filtration. This binding component can be distinguished from one identified in rat serum. Whereas the tissue component sediments in the 2S region of sucrose gradient...