(1) A study of the metabolism of phosphorus in
:bone has been carried out in albino rate with radioactive phosphorus in the normal as well as in induced
pathological conditions and the results have been
(2) It is found that in the normal as well as in
induced rachitic rats, the maximum uptake of marked
phosphorus takes place within six hours after injection. The level of concentration and the rate of deposition of radioactive phosphorus have been found
to be higher in rachitic bones than in the normal and
20 per cent of the injected phosphorus has been found
to be eliminated from bone in twenty-two days.
(3) Using twenty -five Collip units of parathyroi
extract, only 10 per cent phosphorus is mobilised
from bone in two days and with the same dosage,
negligible variation in the total phosphorus content
of bone is observed in twelve hours.
(4) Autoradiographic studies have been undertaken in normal and in induced pathological bones and
a method has been described for obtaining thin
sections of undemineralised bone. Autoradiograms of
bone have been obtained by using a classical technique
and a modification of that technique is described.
The minimum exposure required to obtain clear
autoradiograms of a thin section of rat femur is also