Ergebnisse von Verdrängungsuntersuchungen an Benzodiazepin-Rezeptoren (¹²³J-Jomazenil und Flumazenil)

Zusammenfassung

Bei 14 Patienten mit hepatischer Enzephalopathie wurden SPECT-Unter- suchungen mit ¹²³J-Jomazenil durchgeführt. Der spontane Abfall der Aktivitätskonzentration im Gehirn innerhalb 80 min betrug zwischen 10 und 20%, im Nasenbereich 35%. Nach Injektion von 0,1 bis 0,5 mg Flumazenil wurden innerhalb 20 min bzw. bei Zweitinjektion 29 bis 38% ausgeschwemmt. Eine vergleichbare Ausschwemmung erfolgte in der weißen Substanz und im Nasenbereich. Die Anwendung bekannter Modelle der Rezeptorkinetik war dadurch nicht möglich.

Summary

SPECT studies with ¹²³I-Jomazenil were performed in 14 patients with hepatic encephalopathy. The activity concentration in the brain decreases spontaneously by 10 to 20% within 80 min, in the nasal tissue by 35%. After an i.v. injection of 0.1 to 0.5 mg Flumazenil a decrease of 29 to 38% is observed within 20 min, with a comparable decrease in white matter and nasal tissue. The application of well-known models of receptor kinetics is therefore impossible.

Schlüsselwörter

GABA-Rezeptoren - hepatische Enzephalopathie - SPECT

Keywords

GABA receptors - hepatic encephalopathy - SPECT

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