This is a past event
Ontogeny of unique mammalian behaviours
The growing incidence of obesity and other chronic disorders is alarming. Changes in the metabolic environment during development are important predictors of altered metabolic responses later in life. The Dietrich laboratory overarching goal is to reveal the developmental mechanisms that control homeostasis; understanding these mechanistic details will provide paramount insights into the biology of metabolic disorders, and help develop new strategies to prevent and treat these diseases.
The arcuate nucleus of the hypothalamus harbors discrete populations of neurons that are involved in energy balance regulation. Neurons that express agouti-related peptide (AGRP), neuropeptide Y (NPY), and GABA (AGRP neurons) are involved in food intake, and it has been shown that activation of AGRP neurons promotes voracious feeding in mice.
In addition to feeding, the Dietrich lab has found that activation of AGRP neurons controls foraging and leads to displacement behaviors. AGRP neurons drive this variety of behaviors through the recruitment of several output regions in the brain. Unexpectedly, AGRP neurons densely innervate the ventral tegmental area of the midbrain, where dopamine neurons are located during the first postnatal week in mice, whereas in adults, the innervation from AGRP neurons is substantially reduced. Such findings are surprising and unsuspected, supporting the need of further mechanistic studies in the field of hypothalamic development.
Putative AGRP neurons are generated during an extended time in embryogenesis, starting from embryonic day 11 (E11), after the generation of other neurons of the arcuate nucleus. AGRP neurons then extend their axons to several regions in the brain. Small clusters of cells send axons to specific regions in the brain, but each to a specific region and hemisphere. Remarkably, AGRP neuronal projections are rudimentary at birth, and only develop adult-like connectivity around the third postnatal week in rodents. This delayed maturation is intriguing and it has been hypothesized that AGRP neurons mature at the time of independent food intake, during the process of weaning. The laboratory of Dr Dietrich is investigating in detail the developmental mechanisms underlying AGRP neuronal anatomy and function and the latest findings along these lines of investigation will be presented.
- Speaker
- Marcelo O. Dietrich, Assistant Professor
- Hosted by
- Rowett Institute
- Venue
- The Rowett Institute
- Contact
-
Dr Nigel Hoggard
Tel: 01224 438655
This is a technical seminar aimed at professional scientists. If you are not a University of Aberdeen staff member and would like to attend, please contact us.