University of Manitoba

U of M - Faculty of Science - Biological Sciences - Academic Profile

Academic Profile

Dr. Dirk Weihrauch

Position: Assistant Professor
Department: Biological Sciences
Office: Z418 Duff Roblin
Phone: (204) 474-6310
Fax: (204) 474-7588

The core studies in the laboratory are:

  1. Mechanisms and regulation of excretion of toxic ammonia in invertebrates  and lower vertebrates.
  2. Pathophysiology of ammonia in mammalian systems

In my research program cellular transport of highly toxic ammonia is examined in a variety of different animal systems, including crustaceans, flatworms and frogs. The long term goal of my research is to determine how epithelial transport of ammonia is accomplished in phylogenetic more ancient species with the aim to uncover common mechanisms and strategies that have been evolved in ammoniotelic aquatic invertebrates and vertebrates. The importance for gaining knowledge of ammonia transport mechanisms and its regulation is further given by its direct relevance in the medical field - elevated ammonia levels in mammals cause fatal hepatic encephalopathy - and for economical applications such as aquaculture, where ammonia management is crucial. 

Ammonia transports and its regulation will also be investigated using human colonic cell lines, which generate in culture an artificial epithelium. One focus in all studies are the recently discovered ammonia transporting proteins of the Rhesus-family (Rh-proteins). So far very little is known about their particular role in transepithelial ammonia transport and their regulation.

Students will be trained to examine ammonia balance and ammonia transport mechanisms in an integrative approach (from the whole living animal or the isolated tissue to the underlying molecular mechanisms). Accordingly the students will learn to apply a wide variety of contemporary methods including ion flux measurements, diverse imagine methods, gene expression analysis, gene knock-down techniques and functional protein expression. Communication skills will be trained during regular lab discussions and journal clubs. Further, students will be taught to present their studies at departmental seminars, but also to prepare posters or oral presentations for national and international meetings.     

Courses taught 

ZOOL 3540 Comparative Environmental Physiology
ZOOL 2540 Human Physiology II
BOTN 4460 Molecular Biology of Eukaryotic Cell


Department of Biological Sciences
212B Biological Sciences Building
University of Manitoba, Winnipeg, MB  R3T 2N2 Canada
Tel 204-474-9245  Fax 204-474-7588
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