Abstract |
Using transmission electron microscopy of serially sectioned tentacles from the sea anemone Aiptasia pallida, we located and characterized two types of neuro-spirocyte synapses. Clear vesicles were observed at 10 synapses and dense-cored vesicles at five synapses. The diameters of vesicles at each neuro-spirocyte synapse were averaged; clear vesicles ranged from 49-89 nm in diameter, whereas the dense-cored vesicles ranged from 97-120 nm in diameter. One sequential pair of synapses included a neuro-spirocyte synapse with clear vesicles (81 nm) and a neuro-neuronal synapse with dense-cored vesicles (168 nm). A second synapse on the same cell had dense-cored vesicles (103 nm). An Antho-RFamide-labeled ganglion cell and three different neurites were observed adjacent to spirocytes, but no neuro-spirocyte synapses were present. Many of the spirocytes also were immunoreactive to Antho-RFamide. The presence of sequential neuro-neuro-spirocyte synapses suggests that synaptic modulation may be involved in the neural control of spirocyst discharge. The occurrence of either dense-cored or clear vesicles at neuro-spirocyte synapses suggests that at least two types of neurotransmitter substances control the discharge of spirocysts in sea anemones.
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Authors | J A Westfall, D D Landers, J D McCallum |
Journal | Journal of morphology
(J Morphol)
Vol. 241
Issue 2
Pg. 165-73
(Aug 1999)
ISSN: 0362-2525 [Print] United States |
PMID | 10420162
(Publication Type: Journal Article, Research Support, U.S. Gov't, Non-P.H.S.)
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Copyright | Copyright 1999 Wiley-Liss, Inc. |
Topics |
- Animals
- Microtomy
- Sea Anemones
(ultrastructure)
- Synapses
(ultrastructure)
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