Assuntos
Meios de Contraste/administração & dosagem , Fígado/diagnóstico por imagem , Ácido Metrizoico/administração & dosagem , Tomografia Computadorizada por Raios X , Animais , Meios de Contraste/farmacocinética , Meios de Contraste/toxicidade , Portadores de Fármacos , Neoplasias Hepáticas Experimentais/diagnóstico por imagem , Neoplasias Hepáticas Experimentais/secundário , Masculino , Ácido Metrizoico/farmacocinética , Ácido Metrizoico/toxicidade , Camundongos , Coelhos , Ratos , Ratos EndogâmicosRESUMO
The effects upon the rabbit blood-brain barrier after intracarotid injection of two non-ionic contrast media, iopentol (a monomer) and iodixanol (a dimer) were compared. Iothalamate and iohexol were used as reference substances. 99Tcm-DTPA, 125I-HSA and Trypsin blue were used as tracers in order to demonstrate various degrees of damage to the barrier. Injection of iothalamate led to large extravasation of 99Tcm-DTPA, 125I-HSA and Trypan blue which means severe damage of the blood-brain barrier. Injection of iopentol and iohexol resulted in some extravasation of all three tracers used, whereas injection of iodixanol only led to extravasation of the small molecule tracer 99Tcm-DTPA demonstrating minor changes of the barrier. At computed tomography of the brain with intravascular contrast medium enhancement it is safer to use iodixanol than iothalamate. Iodixanol is expected to cause even less adverse effects to the brain after intraarterial injection than iopentol and iohexol.
Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Meios de Contraste/farmacologia , Animais , Radioisótopos do Iodo , Iohexol/farmacologia , Ácido Iotalâmico/farmacologia , Masculino , Compostos Organometálicos , Concentração Osmolar , Ácido Pentético , Coelhos , Albumina Sérica , Pentetato de Tecnécio Tc 99m , Ácidos Tri-Iodobenzoicos/farmacologia , Azul TripanoRESUMO
The process developed for the synthesis of iopentol consists of several steps. Nine possible impurities from the synthesis of iopentol have been synthesized and one has been isolated from iopentol mother liquor. These substances have been analysed by HPLC methods developed for routine control of iopentol bulk substance. Capacity factors have been calculated for each compound which relate its position in the chromatogram to iopentol. Some of the synthesized compounds have never been found in iopentol and their toxicities have therefore not been determined. Approximate intravenous LD50 values in mice have been determined for the remaining compounds. Taking into consideration these results and the small quantities in which the impurities are present, it is unlikely that they will affect the safety of the final product.
