This work was carried out in the lab of Prof. Susanne Lutz (Institute of Pharmacology and Toxicology) who mentored me through the past four years. I am very grateful for the unwavering support and opportunity you provided me throughout my PhD studies.You always wanted me to succeed and did everything possible to ensure this. You never hesitated to provide me with the needed counselling, help and resources for my work during these years and I am very grateful for that.I also want to express my gratitude to my co-supervisor Prof. Dr. Anne Ridley from King's College London, who has contributed to an enriching international experience, and shared her expertise in Rho-kinases.My sincere gratitude also goes to Prof. Dr. Wolfram-Hubertus Zimmermann, director of the Institute of Pharmacology and Toxicology, at the University of Göttingen, for the opportunity to join an excellent international team and for making available all the technical and intellectual resources to develop my work and grow as a scientist.