Die Embryonalentwicklung der Paradiesschnecke ... - TOBIAS-lib

Kapitel 4
Development of the nervous system in untorted and “normal” M.
cornuarietis
Examinations of embryos incubated with anti-FMRFamide and anti-tubulin
antibodies showed little specific staining and the results are not shown. Thus,
in the following, we exclusively focus on serotonin-like immunoreactivity in
controls and Pt 2+ -exposed embryos. The application of an extended clearing
using the ScaleB4-mixture proved to be essential for the visualization of the
stained structures. Fig. 5 shows the 3D reconstructions of a control embryo
(Fig. 5A,B) and a Pt 2+ -exposed embryo (Fig. 5C,D).
The 3D reconstructions of the control embryo (Fig.
5 A,B) show almost
all elements of the nervous system of M. cornuarietis that should be
present at that age according to Demian and Yousif (1975). Both cerebral
and pedal ganglia can be seen although the two connections between them,
the cerebro-pedal connective and the cerebro-pleural connective, are only
partially stained.
There is also a gap between the subintestinal ganglion
and the pleuro-pedal ganglionic mass and the fusion between these two ganglionic
masses cannot be seen. The connection between the left pleuro-pedal
ganglionic mass and the supraintestinal ganglion is also not stained. The
connection between the supraintestinal ganglion and the right pleuro-pedal
ganglionic mass, the supraintestinal nerve, which crosses from the left side
to the right side, was only partially stained. This connective was added by
hand in Fig. 5A to show the visceral loop more clearly. Fig. 5 C,D shows
a nine days old platinum-exposed sluggish embryo and the structures that
are labeled with an anti-serotonin antibody. The structure is much less clear
than in the control. The only elements that can be distinctly identified are
the pedal ganglia. The visceral ganglion can also be seen in the posterior
region of the embryo although its position is not completely clear. On the
right side of the embryo there is a second ganglionic mass associated with
the pleuro-pedal ganglion: this is probably the subintestinal ganglion that
is fused with this complex. This interpretation is supported by the presence
of a connective between this ganglion and the pleuro-pedal ganglionic mass
on the left side. This connective is most probably the subintestinal nerve
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