Kato M, Blaner W S, Mertz J R, Das K, Kato K, Goodman D S
J Biol Chem. 1985 Apr 25;260(8):4832-8.
Studies were conducted to explore the effects of differences in retinoid nutritional status and of sex on the tissue distribution and levels of cellular retinol-binding protein (CRBP) and of cellular retinoic acid-binding protein (CRABP) in the rat. Sensitive and specific radioimmunoassays were developed and employed to measure the levels of both CRBP and CRABP. Four groups of six male rats each were fed experimental diets that differed greatly in the amount and kind of retinoids provided, but were otherwise identical. These groups were comprised of rats that were normal controls, retinoid-deficient, retinoic acid-fed, and excess retinol-fed. A fifth group of six female rats was fed the control diet. Immunogens identical with rat testis CRBP and CRABP, as assessed by radioimmunoassay displacement curves, were found in every rat tissue examined (21 tissues in males, 18 in females). The highest levels of CRBP were found in the proximal portion of the epididymis, the liver, and kidney. The highest levels of CRABP were found in the seminal vesicles, vas deferens, and skin. A significant (p less than 0.01) inverse relationship was found between CRBP and CRABP levels in the different tissues of the male reproductive tract. In both males and females, CRBP levels were highest in the gonads and proximal portion of the reproductive tract and decreased distally, whereas the opposite was true for CRABP. Retinoid-deficient rats showed reduced tissue levels of CRBP; thus, tissue CRBP levels are influenced by diet and retinoid availability. No differences in tissue CRBP levels were found in the rats fed the control, the retinoic acid, or the excess retinol diets. Female control rats had higher CRBP levels than male controls in 4 of 15 tissues compared (liver, lung, thymus, and fat). In contrast, tissue CRABP levels showed no diet- or sex-dependent differences. Only in one tissue, the skin, were differences observed (lower CRABP in retinoid-deficient and in female rats). Thus, CRABP metabolism and levels appear to be minimally influenced by the amount or kind of retinoid ligand available or by sex.
开展了多项研究，以探究视黄醇营养状况差异及性别对大鼠体内细胞视黄醇结合蛋白（CRBP）和细胞视黄酸结合蛋白（CRABP）的组织分布及水平的影响。开发并采用了灵敏且特异的放射免疫分析法来测定CRBP和CRABP的水平。将四组雄性大鼠（每组六只）分别喂食视黄醇含量和种类差异极大但其他方面相同的实验性日粮。这些组包括正常对照组大鼠、视黄醇缺乏大鼠、喂食视黄酸的大鼠以及喂食过量视黄醇的大鼠。第五组雌性大鼠（六只）喂食对照日粮。通过放射免疫分析置换曲线评估发现，在所检测的每只大鼠组织中（雄性大鼠检测21种组织，雌性大鼠检测18种组织）均存在与大鼠睾丸CRBP和CRABP相同的免疫原。CRBP水平最高的组织为附睾近端、肝脏和肾脏。CRABP水平最高的组织为精囊、输精管和皮肤。在雄性生殖道的不同组织中，发现CRBP和CRABP水平之间存在显著（p小于0.01）的负相关关系。在雄性和雌性大鼠中，CRBP水平在性腺和生殖道近端最高，向远端逐渐降低，而CRABP的情况则相反。视黄醇缺乏的大鼠组织中CRBP水平降低；因此，组织CRBP水平受饮食和视黄醇可用性的影响。喂食对照日粮、视黄酸日粮或过量视黄醇日粮的大鼠组织CRBP水平未发现差异。在15种被比较的组织中的4种组织（肝脏、肺、胸腺和脂肪）中，雌性对照大鼠的CRBP水平高于雄性对照大鼠。相比之下，组织CRABP水平未显示出饮食或性别依赖性差异。仅在一种组织（皮肤）中观察到差异（视黄醇缺乏大鼠和雌性大鼠的CRABP水平较低）。因此，CRABP的代谢和水平似乎受视黄醇配体的量或种类以及性别的影响极小。
