Histological and immunohistochemical studies on spontaneous rat astrocytomas and malignant reticulosis.
Among spontaneous neoplasms of the rat central nervous system, the discrimination between astrocytoma and malignant reticulosis (MR) is sometimes difficult because of their similar cell morphology and infiltration patterns. In the present study, we carried out histological and immunohistochemical analyses on a total of sixty-four cases in Sprague-Dawley and F344 rats. These cases were diagnosed as benign/malignant astrocytoma containing no neoplastic oligodendroglial elements or MR according to the diagnostic criteria of the World Health Organization International Classification of Rodent Tumors (Mohr et al. 1994). Astrocytomas were divided into three types and MR into two types based on the number of lesions, cellularity and infiltration patterns, and so on. Although the neoplastic cells from all types showed various immunoreactivities for RM-4 (anti-rat macrophages and dendritic cells), ED-1, and/or vimentin, there were no distinctive differences among these types, and most cells that were positive for RM-4 were also positive for ED-1. None of the tumor types showed any reactivity for GFAP or S-100 protein. From the results of morphological and immunohistochemical examinations, it was indicated that there are no distinctive differences between spontaneous astrocytomas and MR in rats, and they are probably derived from the same cell lineage, that is, microglia, macrophage, or radial glia.
Nagatani
Mariko
M
Hamamatsu Branch of Pathology Department, Biology and Zoology Research Center Inc., Hamamatsu, Shizuoka 435-0016, Japan. nagatani@bozo.co.jp
Ando
Ryo
R
Yamakawa
Seiki
S
Saito
Tsubasa
T
Tamura
Kazutoshi
K
D000818:Animals; D001254:Astrocytoma / Q000378:metabolism* / Q000473:pathology*; D016543:Central Nervous System Neoplasms / Q000378:metabolism* / Q000473:pathology*; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009836:Oligodendroglia / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D017207:Rats, Sprague-Dawley; D014746:Vimentin / Q000378:metabolism
D009419:Nerve Tissue Proteins; D014746:Vimentin