Female cotton rats (Sigmodon hispidus) develop chronic anemia with renal inflammation and cystic changes.
The cotton rat (Sigmodon hispidus) is a laboratory rodent that has been used for studies on human infectious diseases. In the present study, we observed that female cotton rats, not the male cotton rats, developed chronic anemia characterized by reduced red blood cell, hemoglobin, and hematocrit levels from 5 to 9 months of age without any changes in the mean corpuscular hemoglobin and volume levels. In peripheral blood, the reticulocyte count did not increase in response to anemia in female cotton rats, and no extramedullary hematopoiesis was observed in the liver or spleen. Further, the serum levels of urea nitrogen and creatinine increased from 5 to 9 months of age in female cotton rats compared to male cotton rats, and these increases became more prominent from 10 months of age onward, indicating chronic kidney disease. Histopathologically, female cotton rats manifested tubulointerstitial lesions characterized by the infiltration of mononuclear cells, including plasma cells and CD3(+) T-cells, as well as the dilation of calbindin-D28k(+) distal tubules from 5 to 9 months of age. The severity of these lesions progressed from 10 months of age onward, and renal fibrotic features and numerous tubular cysts appeared without any obvious glomerular lesions. A significant decrease in the erythropoietin protein levels was observed in the kidney of aged female cotton rats, and significant correlations were detected between anemia and tubulointerstitial damage. These results suggest that aged female cotton rats chronically develop renal anemia, and this rodent may serve as a novel model to elucidate its pathogenesis.
Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18-Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan. ichi-o@vetmed.hokudai.ac.jp.
Osamu
O
Ichii
Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18-Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan.|Section of Biological Safety Research, Chitose Laboratory, Japan Food Research Laboratories, Chitose, Hokkaido, Japan.
Teppei
T
Nakamura
Medical Zoology Group, Department of Infectious Diseases, Hokkaido Institute of Public Health, Sapporo, Hokkaido, Japan.
Takao
T
Irie
Medical Zoology Group, Department of Infectious Diseases, Hokkaido Institute of Public Health, Sapporo, Hokkaido, Japan.
Hirokazu
H
Kouguchi
Sankyo Labo Service Corporation, Inc., Tokyo, Japan.
Daisuke
D
Nakamura
Sankyo Labo Service Corporation, Inc., Tokyo, Japan.
Saori
S
Nakamura
Sankyo Labo Service Corporation, Inc., Tokyo, Japan.
Shinobu
S
Sato
Sankyo Labo Service Corporation, Inc., Tokyo, Japan.
Keisuke
K
Yokoyama
Department of Endocrinology, Metabolism and Nephrology, Kochi Medical School, Kochi University, Nankoku, Kochi, Japan.
Taro
T
Horino
Laboratory of Veterinary Pathology, Faculty of Agriculture, Tottori University, Tottori, Japan.
Yuji
Y
Sunden
Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18-Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan.|Department of Histology and Cytology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
Yaser Hosny Ali
YH
Elewa
Laboratory of Anatomy, Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18-Nishi 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan.
Yasuhiro
Y
Kon
D000740:Anemia / Q000378:metabolism / Q000473:pathology*; D000818:Animals; D002908:Chronic Disease; D004195:Disease Models, Animal; D005260:Female; D007249:Inflammation / Q000378:metabolism / Q000473:pathology*; D052177:Kidney Diseases, Cystic / Q000378:metabolism / Q000473:pathology*; D008297:Male; D012727:Sex Characteristics; D016205:Sigmodontinae
Anemia; Cotton rat; Cystic lesion; Inflammation; Kidney