[Effects of excess fluoride on bone turnover under conditions of diet with different calcium contents].
OBJECTIVE
To study the effects of excess fluoride on bone turnover under conditions of diet containing different amount of calcium.


METHODS
The experiment was performed on rats raised on a balanced diet with adequate calcium or a monotonous diet with low calcium and given amount of fluoride in their drinking water (F, 100 mg/L) for 2 months or 1 year.


RESULTS
Osteomalacia, osteoporosis and accelerated bone turnover were observed with elevated serum alkaline phosphatase (ALP), osteocalcin (BGP) and parathyroid hormone (PTH) in rats fed on low calcium diet and fluoridized water for 2 months. In the rats fed on adequate calcium diet and fluoridized water for 2 months, only slightly increased osteoblastic activity was found while the average width of trabecular bone was increased with elevated serum ALP activity in rats raised on the same diet and water for 1 year.


CONCLUSIONS
The basic effect of excess fluoride on bone is the causation of a high bone turnover state which can also be induced to a milder extent by low calcium diet itself. Therefore, the formation of a high bone turnover state is the pathogenetic basis for low dietary calcium intake to exacerbate the severity of skeletal fluorosis.
Li
G
G
Institute of Endemic Diseases, Norman Bethune University of Medical Sciences, Changchun.
Ren
L
L
D000469:Alkaline Phosphatase / Q000097:blood; D000818:Animals; D002118:Calcium / Q000097:blood* / Q000172:deficiency; D005260:Female; D005458:Fluoride Poisoning / Q000097:blood / Q000150:complications* / Q000473:pathology; D005526:Food, Formulated; D008297:Male; D015675:Osteocalcin / Q000097:blood; D010018:Osteomalacia / Q000209:etiology*; D010024:Osteoporosis / Q000209:etiology*; D010281:Parathyroid Hormone / Q000097:blood; D051381:Rats
D010281:Parathyroid Hormone; D015675:Osteocalcin; D000469:Alkaline Phosphatase; D002118:Calcium