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Abstract Recent years have led to increased effort to describe and understand the peripheral nervous system and its influence on central mechanisms and behavior in gastropod molluscs. This study revealed that an antibody raised against keyhole limpet hemocyanin (KLH) cross‐reacts with an antigen(s) found extensively in both the central and the peripheral nervous systems ofBiomphalaria alexandrina. The results revealed KLH‐like immunoreactive (LIR) neurons in the cerebral, pedal, buccal, left pleural, right parietal, and visceral ganglion within the CNS with fibers projecting throughout all the peripheral nerves. Numerous KLH‐LIR peripheral sensory neurons located in the foot, lips, tentacles, mantle, esophagus, and penis exhibited a bipolar morphology with long tortuous dendrites. KLH‐LIR cells were also present in the eye and statocyst, thus suggesting the labeling of multiple sensory modalities/cell types. KLH‐LIR cells did not co‐localize with tyrosine hydroxylase (TH)‐LIR cells, which have previously been described in this and other gastropods. The results thus provide descriptions of thousands of peripheral sensory neurons, not previously described in detail. Future research should seek to pair sensory modalities with peripheral cell type and attempt to further elucidate the nature of KLH‐like reactivity. These findings also emphasize the need for caution when analyzing results obtained through use of antibodies raised against haptens conjugated to carrier proteins, suggesting the need for stringent controls to help limit potential confounds caused by cross‐reactivity. In addition, this study is the first to describe neuronal cross‐reactivity with KLH inBiomphalaria, which could provide a substrate for host‐parasite interactions with a parasitic trematode,Schistosoma.
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This content will become publicly available on April 27, 2026
Dopaminergic Central Neurons and Peripheral Sensory Systems in Pteropod and Nudibranch Molluscs
ABSTRACT In Euthyneuran molluscs, the distribution and plethora of dopamine (DA) functions are likely coupled to the feeding ecology with a broad spectrum of modifications both in the central and peripheral neural systems. However, studies of benthic grazers currently dominate the analysis of DA‐mediated signaling, whereas adaptations to pelagic lifestyles and other feeding strategies are unknown. Here, we characterize the distribution of central and peripheral neurons in representatives of distinct ecological groups: the pelagic predatory pteropodClione limacina(Pteropoda, Gymnosomata) and its prey —Limacina helicina(Pteropoda, Thecosomata), as well as the plankton eaterMelibe leonina(Nudipleura, Nudibranchia). By using tyrosine hydroxylase immunoreactivity as a reporter, we mapped their dopaminergic systems. Across all studied species, despite their differences in ecology, small numbers of dopaminergic neurons in the central ganglia contrast to an incredible density of these neurons in the peripheral nervous system, primarily representing sensory‐like cells, which are predominantly concentrated in the chemotactic areas and project afferent axons to the central nervous system. Combined with tubulin immunoreactivity, this study illuminates the complexity of sensory signaling and peripheral neural systems in Euthyneuran molluscs with lineage‐specific adaptations across different taxonomical and ecological groups.
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- Award ID(s):
- 2341882
- PAR ID:
- 10585547
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Comparative Neurology
- Volume:
- 533
- Issue:
- 5
- ISSN:
- 0021-9967
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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