Daniela Nürnberg

Zusammenfassung: Die Bildgebung von intraokularen Tumoren ist multimodal, vielseitig einsetzbar, in stetiger Weiterentwicklung. Sie ist damit unerlässlich für die Erkennung, Diagnose, Therapieplanung und Überwachung von intraokularen Tumoren. Für die Diagnostik und Verlaufskontrolle steht ein breites Spektrum bildgebender Verfahren zur Verfügung: die Farbbildaufnahme, Infrarotaufnahme, Autofluoreszenzaufnahme, Fluoreszenzangiografie (FAG) und Indocyaningrünangiografie (ICGA), optische Kohärenztomografie (OCT) und die Sonografie (US). In dieser Arbeit wird an verschiedenen Beispielen die multimodale Nutzung von Bildgebungsverfahren in der Diagnose, Therapie und Nachsorge okulärer Tumoren unter besonderer Berücksichtigung der Aderhautmelanome beschrieben.

The thyroid hormone derivative 3-iodothyronamine (3-T₁AM) exerts metabolic effects in vivo that contradict known effects of thyroid hormones. 3-T₁AM acts as a trace amine-associated receptor 1 (TAAR1) agonist and activates G_s signaling in vitro. Interestingly, 3-T₁AM-meditated in vivo effects persist in Taar1 knockout-mice indicating that further targets of 3-T₁AM might exist. Here, we investigated another member of the TAAR family, the only scarcely studied mouse and human trace-amine-associated receptor 8 (Taar8b, TAAR8). By RT-qPCR and locked-nucleic-acid (LNA) in situ hybridization, Taar8b expression in different mouse tissues was analyzed. Functionally, we characterized TAAR8 and Taar8b with regard to cell surface expression and signaling via different G-protein-mediated pathways. Cell surface expression was verified by ELISA, and cAMP accumulation was quantified by AlphaScreen for detection of G_s and/or G_i/o signaling. Activation of G-proteins G_q/11 and G_12/13 was analyzed by reporter gene assays. Expression analyses revealed at most marginal Taar8b expression and no gender differences for almost all analyzed tissues. In heart, LNA-in situ hybridization demonstrated the absence of Taar8b expression. We could not identify 3-T₁AM as a ligand for TAAR8 and Taar8b, but both receptors were characterized by a basal G_i/o signaling activity, a so far unknown signaling pathway for TAARs.