Radiology, Vol 142, 115-118, Copyright © 1982 by Radiological Society of North America
Nonionic dimer: development and initial testing of an intrathecal contrast agent
M Sovak, R Ranganathan and U Speck
A nonionic dimer (DL-3-117) containing a novel substituent (D,L amino-
threitol) was synthesized and tested as an intrathecal contrast medium. In
the complement-mediated assay, the dimer was approximately half as
inhibitory of hemolysis as metrizamide or iopamidol. The lethal dose (LD50)
in protozoa was 320 mg I/ml for DL-3-117, 96 mg I/ml for metrizamide, and
101 mg I/ml for iopamidol. The intravenous LD50 of DL- 3-117 in mice was 26
g/kg, and in rats it was 12.7 g/kg. The effective dose (ED50) of
intradiencephalic injection in rats was 219 mg I/kg for DL-3-117, 61.9 mg
I/kg for metrizamide, and 154.1 mg I/kg for iopamidol, which are
significantly different. A dose of 300 mg I/kg injected into a permanently
cannulated lateral ventricle produced neurofunctional deficits with all
contrast media except DL-3-117, which scored equal to Ringer's solution.
Metrizamide and iopamidol in the same model, adapted for aversion
conditioning, induced aversion with 45 mg I/kg, while DL-3-117 did not
condition the rats.
