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The development of bone changes induced in rats by recombinant
human granulocyte colony-stimulating factor is suppressed by bisphosphonate
M. Suzuki1,2, K. Adachi2, T. Sugimoto2, H.
Nakayama1 and K. Doi1
1Department of Veterinary Pathology, Faculty
of Agriculture, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
and 2Toxicology Laboratory, Chugai Pharmaceutical Co., Ltd., Gotemba-shi,
Shizuoka, Japan
Offprint requests to: Dr.
Masami Suzuki, Toxicology Laboratory, Chugai Pharmaceutical Co.,
Ltd., 1-135 Komakado, Gotemba-shi, Shizuoka 412-8513, Japan
Summary. We have
previously demonstrated that high doses of recombinant human granulocyte
colony-stimulating factor (rhG-CSF) induce bone changes characterized
by osteoclastic bone resorption and osteogenesis due to intramembranous
ossification in rats. In this communication we examined the effects
of a pretreatment with 3-amino-1-hydroxypropylidene-1,1-bisphosphonate
(AHPrBP), which is a powerful inhibitor of osteoclastic bone resorption,
on bone changes induced by rhG-CSF in order to investigate the
relation between osteoclastic bone resorption and osteogenesis.
AHPrBP (5 mg/kg/day) was subcutaneously given to 6-week-old rats
for 2 days. From the following day of the final injection of AHPrBP,
rats received a subcutaneous injection of rhG-CSF (1,000 µg/kg/day)
for 14 days, and the femur and tibia were evaluated histopathologically.
By the analysis of peripheral blood leukocyte counts, spleen weights
and bone marrow findings, the pretreatment with AHPrBP had no
effect on the activation of hematopoiesis related to the major
pharmacological activity of rhG-CSF. In the rats treated with
rhG-CSF alone, accelerated osteoclastic bone resorption and osteogenesis
due to intramembranous ossification were observed in the trabeculae
of metaphyseal spongiosa. The accelerated osteoclastic bone resorption
induced by rhG-CSF was suppressed by the pharmacological activity
of AHPrBP. Furthermore, the osteogenesis induced by rhG-CSF was
also suppressed by AHPrBP. These results suggest that the osteogenesis
induced by rhG-CSF is a sequential reaction of accelerated osteoclastic
bone resorption, and moreover that the main action of rhG-CSF
on bone is an acceleration of osteoclastic bone resorption. Histol.
Histopathol. 14, 679-686 (1999)
Key words: Granulocyte
colony-stimulating factor, Osteoclastic bone resorption, Osteogenesis,
Intra-membranous ossification, Bisphosphonate
DOI: 10.14670/HH-14.679
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