title: Study on the pathogenesis of foreign body granulomatous inflammation in the livers of sprague-dawley rats.
abstract: Focal granulomatous inflammation developed in the livers of five 10-week-old male Sprague-Dawley rats. The characteristic features of this lesion were the presence of foreign body multinucleated giant cells engulfing calcium deposits and site-specific development in a fissure formed in a sub-lobation in the left lobe or interlobar fissure of the medial lobe of the liver. To clarify the pathogenesis of this lesion, rat livers showing abnormal sub-lobation or lobar atrophy, rat livers in an acute dermal toxicity study and guinea pig livers in a skin sensitization test were also examined histologically. Consequently, the present lesion was considered to be a reactive change against calcium that was dystrophically deposited in the area of hepatocellular necrosis due to delayed circulatory disturbance caused by external pressure or extension force. Granulomatous lesions like in the present cases should be differentiated from those caused by evident exogenous pathogens such as chemicals or microorganisms.
authors.affiliation: Biosafety Research Center, Foods, Drugs and Pesticides (BSRC), 582-2 Shioshinden, Iwata-shi, Shizuoka 437-1213, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Shiga
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Ota
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Ueda
authors.forename: Masayo
authors.initials: M
authors.lastname: Hosoi
authors.forename: Rumiko
authors.initials: R
authors.lastname: Miyajima
authors.forename: Kazushige
authors.initials: K
authors.lastname: Hasegawa
authors.forename: Fukutaro
authors.initials: F
authors.lastname: Mizuhashi