The biodistribution of NC100668 and the effect of excess NC100668 on the biodistribution and kidney retention of 99mTc-NC100668 in the rat

The biodistribution and blood clot uptake of 99mTc-NC100668 and [Asn-U-14C]NC100668 are similar. With the exception of the kidneys, 99mTc-NC100668 biodistribution and blood clot uptake are unaffected by the presence of unlabelled NC100668. The kidney retention of radioactivity is probably due to transglutaminase activity and, to a lesser extent, nonspecific charge-mediated endocytosis.