Jørgensen, Even

Date of birth: 15.06.54

Place of birth: Lavangen, North-Norway

Leader, teaching group in fish ecophysiology and aquaculture

My research interest revolves around the fascinating adaptations that have developed in fish that are living in the hash and strongly seasonal environment of the high north. The anadromous (sea-migrating) life strategy of the northernmost fresh water fish species, the Arctic charr (Salvelinus alpinus) is the dominating, highly esteemed research model. This model is used to reveal how the substantial seasonal transitions between voluntary anorexia (winter) and hyperphagia (summer) in the anadromous Arctic charr is made possible within a lipostatic model of appetite regulation, both to gain knowledge about how high-latitude animals cope with their environment and how neuroendocrine mechanisms regulate and control appetite and energy homeostasis in animals in general. Further, there is a focus on how the endocrine axes related to the regulation of growth, and stress responses, integrate with the mechanisms regulating appetite. Studies are undertaken both under controlled conditions in the laboratory and in the field and although most of this research may be encompassed within the term "basic research", the knowledge obtained is considered important both for future management of high-latitude fish and farming of such species.

TEMPANAT: Molecular Adaptations to Temperature Changes: the Fish Arylalkylamine N-Acetyltransferase. In collaboration with Dr. Jack Falcon, Université Pierre et Marie Curie, France. Agence Nationale de la Recherche.

Physiological mechanisms underlying the seasonal changes in appetite in Arctic charr. PhD project, University of Tromsø.

The role of melationin in the regulation of seasonal cycles in Arctic charr. Post-doc project, University of Tromsø.

Paracrine and endocrine roles of leptin in the regulation of appetite and energy homeostasis in fish. Two master projects, University of Tromsø.

Recent publications:

Sonne, C., Wolkers, H., Leifsson,P.S., Iburg, T., Jenssen, B.M., Fuglei, E., Ahlstrøm, A., Dietz, R., Kirkegaard, M., Muir, D.C.GH. and Jørgensen, E.H. 2009. Chronic dietary exposure to environmental organochlorine contaminants induces thyroid gland lesions in Arctic foxes (Vulpes lagopus). Env. Res. 109, 702-711.

Ojima, D., Pettersen, R.J., Wolkers, J., Johnsen, H.K. and Jørgensen, E.H. 2009. Growth hormone and cortisol treatment stimulate seawater tolerance in both anadromous and landlocked Arctic charr. Comp. Biochem. Physiol. 153, 378-385.

Lays, N., Thode Iversen, M.M., Frantzen, M. and Jørgensen, E.H. 2009. Physiological stress responses in spotted wolffish (Anarhichas minor) subjected to acute disturbance and progressive hypoxia. Aquaculture., 295, 126-133.

Frøiland, E., Murashita, K., Jørgensen, E.H. and Kurokawa, T. 2010. Leptin and ghrelin in anadromous Arctic charr: cloning and change in expressions during a seasonal feeding cycle. Gen. Comp. Endocrinol. 165, 136-143.

Aarseth, J.J., Frøiland, E. and Jørgensen, E.H. Melatonin implantation during spring and summer does not affect seasonal rhythms of feeding and maturation in anadromous Arctic charr (Salvelinus alpinus). Polar Biology. J. Polar Biol., Accepted.

Letcher, R.J., Bustnes, J.O., Dietz, R., Jenssen, B.M., Jørgensen, E.H., Sonne, C., Verreault, J., Vijayan, M.M. and Gabrielsen, G.W. 2009. Effects assessment of persistent organohalogen contaminants in arctic wildlife and fish. Sci. Tot. Environ. Review article, accepted.