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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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This content will become publicly available on May 1, 2026
Identified neurons B4/B5 function as sensory neurons, motor neurons, and interneurons in Aplysia
The B4/B5 neurons in Aplysia californica have multiple functions. In this study, we further characterized B4/B5’s sensory responses to mechanical stimuli at different locations in the feeding apparatus and identified their direct motor effect on the muscles. The bidirectional signaling of B4/B5, which was also observed in freely feeding animals, suggests that these neurons may play a role in detecting nociceptive or proprioceptive information and regulating the movements that facilitate particular feeding behaviors.
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- Award ID(s):
- 2015317
- PAR ID:
- 10627474
- Publisher / Repository:
- American Physiological Society
- Date Published:
- Journal Name:
- Journal of Neurophysiology
- Volume:
- 133
- Issue:
- 5
- ISSN:
- 0022-3077
- Page Range / eLocation ID:
- 1435 to 1455
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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