Dear friends - We have 25 rats, 14 of these subjected to partial removal
of kidney tissue, 11 to sham operation, and then followed for 6 weeks.
So far we have data on 26 urine metabolites measured by NMR 7 times
during the observation. I have smoothed the measurements by b.splines in
fda including a roughness penalty, and inspecting the mean curves for
nephrectomized and sham animals indicate differences for several of the
metabolites. Now the real idea is to use the NMR measurements to
understand what goes on in the kidneys since we know the partial removal
of kidney tissue will result in progressive damage in the kidneys - the
nature of that is what we want to understand. We have a blood sample
from the rats just prior to sacrifice, and the creatinine concentration
there is a good proxy for "renal function". So the course of
concentrations of the metabolites are thought to be valuable in
understanding the physiology. Some of these are thought to be
correlated. We have two groups where sham animals have better renal
function than partially nephrectomized, but there is variation in both
groups which is also interesting - some animals progress more rapidly
after "the same operation" than others - we would like to know why.
The data are available (eventually - the resulting blood tests still are
missing) if anyone would like to have a look but the main issue is if it
is at all feasible to make fda work on such a problem.
Best wishes
Troels Ring,
Nephrology
Aalborg, Denmark
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