In vivo manganese-enhanced magnetic resonance imaging reveals connections and functional properties of the songbird vocal control system.
Injection of manganese (Mn(2+)), a paramagnetic tract tracing agent and calcium analogue, into the high vocal center of starlings labeled within a few hours the nucleus robustus archistriatalis and area X as observed by in vivo magnetic resonance imaging. Structures highlighted by Mn(2+) accumulation assumed the expected tri-dimensional shape of the nucleus robustus archistriatalis and area X as identified by classical histological or neurochemical methods. The volume of these nuclei could be accurately calculated by segmentation of the areas highlighted by Mn(2+). Besides confirming previously established volumetric sex differences, Mn(2+) uptake into these nuclei revealed new functional sex differences affecting Mn(2+) transport. A faster transport was observed in males than in females and different relative amounts of Mn(2+) were transported to nucleus robustus archistriatalis and area X in males as compared to females. This new in vivo approach, allowing repeated measures, opens new vistas to study the remarkable seasonal plasticity in size and activity of song-control nuclei and correlate neuronal activity with behavior. It also provides new insights on in vivo axonal transport and neuronal activity in song-control nuclei of oscines.
Van der Linden
A
A
Bio-Imaging Laboratory, RUCA, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. avadelin@ruca.ua.ac.be
Verhoye
M
M
Van Meir
V
V
Tindemans
I
I
Eens
M
M
Absil
P
P
Balthazart
J
J
D000818:Animals; D001692:Biological Transport / Q000502:physiology; D001921:Brain / Q000033:anatomy & histology / Q000502:physiology*; D005260:Female; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008345:Manganese / Q000008:administration & dosage / Q000032:analysis / Q000493:pharmacokinetics*; D008845:Microinjections; D015203:Reproducibility of Results; D012727:Sex Characteristics; D012737:Sex Factors; D020308:Songbirds / Q000502:physiology*; D013238:Stereotaxic Techniques; D014828:Vocalization, Animal / Q000502:physiology*
D008345:Manganese