
the role of age and x-irradiation on kidney
function in the mouse
female mouse kidneys show a decline with respect to age in the ability to
concentrate the urine during a 24-hour water fast.  x-irradiation early in
life has no measurable long-term effect on this process.
kidney cortex slices of old female mice can concentrate p-aminohippuric
acid against a concentration gradient equally as well as slices from young
mice.  there is no loss in this ability by cortex slices from young or old
female x-irradiated mice.
it is uncertain whether compensatory renal hypertrophy after unilateral
nephrectomy declines with age in nonirradiated mice.  x-irradiation does
cause a reduction in the degree of compensatory renal hypertrophy in the aging
mouse.  this reduction may represent a loss in the ability of kidney cells to
undergo cell division.
the administration of testosterone propionate to old mice during compen-
satory renal hypertrophy results in an increased hypertrophy.  the increase is
relatively the same for irradiated and nonirradiated mice, indicating the lack
of a long-term effect of x-irradiation to reduce the ability of a target
organ to respond to a hormone.
the over-all conclusion of this study, with respect to "radiation-induced
aging," is that x-irradiation of the female swiss mouse early in life does not
have a pronounced effect on kidney function late in life but may have a long-
term effect on those processes concerned with cell division.
