N-Isopropyl-¹²³I-p-lodoamphet- amine Uptake Mechanism in the Lung - Is it Dependent on pH, Lipophilicity or pK_a?

The uptake and binding mechanism of biogenic amines in the lungs has been studied extensively with no conclusive results. The competition between N-isopropyl-¹²³I-p-iodo amphetamines (¹²³I-IMP) and propranolol and ¹²³I-IMP and ketamine, in the lungs suggest that the pK_a value of the biogenic amines has a significant role to play in the mechanism of uptake and retention of biogenic amines in the lungs.

Zusammenfassung

Der Mechanismus der Aufnahme mit Bindung biogener Amine in der Lunge wurde gründlich, jedoch ohne überzeugende Ergebnisse untersucht. Der Wettbewerb zwischen n-Isopropyl-¹²³J-p-Iodamphetamin und Propranolol sowie zwischen ¹²³J-IMP und Ketamin in der Lunge legt nahe, daß der pK_a-Wert der biogenen Amine eine wichtige Rolle im Mechanismus der Aufnahme und Rückhaltung biogener Amine in der Lunge spielt.

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