一本道

Photo of Michal Pietrzak

Michal Pietrzak

Resident Physician at the University Hospital in 一本道 and PhD student at CSAN.

Ongoing research projects

  • ”Behavioral, affective and cognitive consequences of bariatric surgery”
  • ”Effects of the appetite-inducing hormone ghrelin on decision making in healthy volunteers”

Ghrelin, a hormone produced in the stomach, is the endogenous ligand for the growth hormone secretagogue receptor (GHSR), and promotes appetite through hypothalamic actions. GHS-R is also expressed in brain areas involved in motivation and decision-making, such as the mesolimbic dopamine (DA) pathway. Reduction of ghrelin levels is thought to be an important mechanism contributing to the weight loss following bariatric surgery. Findings also have shown that ghrelin influences drug- and food reward as well as novelty seeking. Finally, ghrelin also plays a role in integrating central circuitry involved in anxiety and responses to stress.

Decision making processes that involve reward and risk assessment subserve the solution of the tradeoff between exploiting available resources vs exploring the environment for novel resources. We hypothesize that these processes are modulated by signals that communicate the availability of food.

Publications

2026

Michal Pietrzak, Beatrice Huhta, Adam Yngve, Emelie Gauffin, Andreas L枚fberg, Lars 脰stman, Emil Persson, L. Leggio, Andrea Johansson Capusan, Gustav Tingh枚g, Markus Heilig (2026) Neuroscience Applied, Vol. 5, Article 106873 (Article in journal)
Andreas L枚fberg, Nicholas Harp, Irene Perini, Robin K盲mpe, Hanna Karlsson, Michal Pietrzak, Hedy Kober, Markus Heilig (2026) Neuropsychopharmacology (Article in journal)

2025

Paula Salamone, Adam Enmalm, Reinoud Kaldewaij, Marie 脜man, Charlotte Medley, Michal Pietrzak, H氓kan Olausson, Andrea Johansson Capusan, Rebecca B枚hme (2025) Molecular Psychiatry, Vol. 30, p. 5417-5426 (Article in journal)
Leah Mayo, Emelie Gauffin, Gavin N. Petrie, Ryann Tansey, Raegan Mary Rose Mazurka, Connor James Haggarty, Madeleine Jones, Hilda Engelbrektsson, Victoria Aminoff, Anisja Huhne-Landgraf, Mark E. Schmidt, Darrel J. Pemberton, Cecilia Fredlund, Lars 脰stman Vasko, Hanna Karlsson, Andreas L枚fberg, Michal Pietrzak, Gerhard Andersson, Andrea Johansson Capusan, Matthew N. Hill, Markus Heilig (2025) Neuropsychopharmacology, Vol. 50, p. 1564-1572 (Article in journal)

2024

Reinoud Kaldewaij, Paula Salamone, Adam Enmalm, Lars 脰stman Vasko, Michal Pietrzak, Hanna Karlsson, Andreas L枚fberg, Emelie Gauffin, Martin Samuelsson, Sarah Gustavson, Andrea Johansson Capusan, H氓kan Olausson, Markus Heilig, Rebecca B枚hme (2024) Neuropsychopharmacology, Vol. 49, p. 1767-1774 (Article in journal)

Research

Organisation