Abstract
A. Sodium fluorid. This was administered to rats in their food, for continuous periods up to twenty-one weeks: followed in some cases by after-periods of unpoisoned food. The effects differ quantitatively according to the daily dosage.
Daily doses of 42 to 151 mgm. of NaF per kilogram of rats produced very marked retardation of growth, starting with the administration, and increasing with the dosage. The damage is persistent, i.e., if the administration of the drug is stopped, growth returns toward normal; but not sufficiently to make up materially in twelve weeks, the loss that occurred during the drug period.
The food-consumption is generally diminished, parallel to the growth. This is not due to distaste for the food; for except with the highest concentration, the rats did not discriminate against the poisoned food, when permitted equal access to unpoisoned food.
The highest of these fluorid doses (151 mgm.) is uniformly fatal within eleven weeks. Doses of 87 mgm. or smaller, for long periods, apparently are not fatal; for the mortality of the animals was small, no greater than that of control animals.
Daily doses of 15 to 20 mgm. of NaF per kilogram of rats produced after a time moderate but definite interference with the growth and food consumption. This effect may occur early, or be delayed for fifteen weeks. Recovery of normal weight on unpoisoned food is slow and imperfect.
Daily doses of 0.15 to 8 mgm. of NaF per kilogram of rats for nine weeks did not perceptively affect growth or food consumption
B. Sodium chlorid. Concentrations of NaCl equivalent to the highest concentrations of NaF, when added to the standard food, do not diminish the growth or food consumption. The latter indeed appears larger than usual; but this may be accidental.
C. "Phosphate rock." Fluorid in this form has approximately the same deleterious effects as corresponding doses in the form of NaF.
D and E. Calcium phosphate or calcium carbonate. In doses corresponding to those of "phosphate rock," these do not depress growth or appetite. Indeed, the food consumption was generally much better than usual; but this again might have been accidental.
Footnotes
- Received December 16, 1920.
JPET articles become freely available 12 months after publication, and remain freely available for 5 years.Non-open access articles that fall outside this five year window are available only to institutional subscribers and current ASPET members, or through the article purchase feature at the bottom of the page.
|