|
| |
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
|
Fig. 4. Hemolymph lacunae are coincident with areas of immunolabel avoidance in the
anterior commissural organ (ACO). In the commissural ganglion, the substance
P-immunopositive plexus is fenestrated by what appears to be a network of
branched tubes. To determine if these tubular structures are hemolymph
lacunae, several India ink-filled ganglia were immunoprocessed with the
substance P antibody, and the ink and immunolabel were simultaneously imaged
via confocal microscopy. As can be seen in this set of micrographs,
ink-filling (A) was evident in numerous lacunae in the portion of the ganglion
containing the substance P-immunopositive plexus (B). When micrographs of the
individual labels were merged (C), it became apparent that the plexus is
fenestrated by hemolymph vessels. As the merged micrograph shows, the
substance P-immunopositive nerve terminals that form the plexus envelop the
hemolymph lacunae. This organization, with nerve terminals in direct
apposition to the hemolymph space, is considered the defining characteristic
of a crustacean neuroendocrine site. We hypothesize that this plexus is a
neuroendocrine organ and we have named it the anterior commissural organ based
on its location. Each micrograph is a brightest pixel projection of nine
optical sections taken at 0.5 µm intervals. A and B are shown at the same
scale. Scale bars, 20 µm in B and C.
|
