ERYTHROPOIETIC PROPHYRIA OF FOX SQUIRREL SCIURUS-NIGER
ERYTHROPOIETIC PROPHYRIA OF FOX SQUIRREL SCIURUS-NIGER
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DOI：
10.1172/jci107178
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发表时间：
1973-01-01
影响因子：
15.9
通讯作者：
FLYGER, V
中科院分区：
文献类型：
--
作者：
LEVIN, EY;FLYGER, V
尿卟啉I在狐狸松鼠的骨骼、牙齿、血液、软组织和尿液中浓度很高。狐松鼠脾脏中尿卟啉的浓度远高于肝、肾和骨髓，可能是由于吞噬红细胞的蓄积所致。出血导致红细胞和脾的尿卟啉浓度显著增加，尿卟啉排泄增加3-8倍。狐松鼠尿中δ-氨基乙酰丙酸和胆色素原的排泄量并不比非斑状灰松鼠多。在所有这些特征中，以及先前证明的红细胞中尿卟啉原III合成酶的缺乏，狐狸松鼠的生理性卟啉症类似于先天性红细胞生成性卟啉症，这是一种人和牛的遗传性疾病。对于松鼠不同的是，没有证据表明皮肤光敏性或溶血性贫血。尿卟啉原III合成酶活性存在于狐狸松鼠骨髓中，其浓度为灰松鼠骨髓的1/10。狐狸松鼠酶比灰松鼠酶更不稳定，这为它的低活性和尿卟啉I的过量生产提供了一个可能的解释。由于狐和灰松鼠血中尿卟啉原I合成酶的活性相同，故尿卟啉原I合成酶的失活不可能导致共合成酶的缺乏，狐松鼠卟啉症为研究人类先天性红细胞生成性卟啉症的发病机制提供了一个方便的模型。
Uroporphyrin I is found in high concentration in the bones, teeth, blood, soft tissues, and urine of the fox squirrel,Sciurus niger. The concentration of uroporphyrin in fox squirrel spleen is much higher than in liver, kidney or bone marrow, probably because of accumulation from phagocytosed red cells. Bleeding causes a marked increase in the uroporphyrin concentration of red cells and spleen, and a 3-8-fold increase in uroporphyrin excretion. Urinary excretion of δ-aminolevulinic acid and porphobilinogen is not greater in fox squirrels than in nonporphyric gray squirrels.Sciurus carolinensis, used as controls. In all these characteristics, as well as in the previously demonstrated deficiency of the enzyme uroporphyrinogen III cosynthetase in red cells, the physiological porphyria of fox squirrels resembles congenital erythropoietic porphyria, a hereditary disease of man and cattle. For squirrels differ in showing no evidence of cutaneous photosensitivity or hemolytic anemia.Uroporphyrinogen III cosynthetase activity is present in fox squirrel bone marrow at 1/10 its concentration in gray squirrel marrow. The fox squirrel enzyme is much more unstable than the gray squirrel enzyme, which provides a possible explanation for its low activity and for the overproduction of uroporphyrin I. It is unlikely that the deficiency of cosynthetase is due to its inactivation by excessive amounts of uroporphyrinogen I synthetase, because activity of the latter enzyme is the same in blood from fox and gray squirrels.Fox squirrel porphyria provides a convenient model for studies of pathogenesis of human congenital erythropoietic porphyria.