Research output: Contribution to journal › Article › peer-review
Fine structure of the nervous system of Cercaria parvicaudata Stunkard & Shaw, 1931 (Digenea, Renicolidae). / Denisova, Sofia A.; Shchenkov, Sergei V. .
In: Journal of Morphology, Vol. 281, No. 7, 21137, 01.07.2020, p. 765-777.Research output: Contribution to journal › Article › peer-review
}
TY - JOUR
T1 - Fine structure of the nervous system of Cercaria parvicaudata Stunkard & Shaw, 1931 (Digenea, Renicolidae)
AU - Denisova, Sofia A.
AU - Shchenkov, Sergei V.
N1 - Publisher Copyright: © 2020 Wiley Periodicals, Inc.
PY - 2020/7/1
Y1 - 2020/7/1
N2 - The biology of free‐living and parasitic Platyhelminthes is diverse. Taking into account the widespread prevalence of parasitic flatworms, Digenea is the least studied group regarding the fine structure of nervous system especially of the cercarial life stage. Here, we present a description of the fine structure of central nervous system (CNS) and two types of uniciliate sensory papillae of xiphidiocercaria Cercaria parvicaudata (Microphalloidea, Renicolidae). The present study documents that C. parvicaudata has a complex nervous system that includes a well‐developed ganglion with a cortex of perikarya and glia‐like sheaths, myelin‐like structures within one of the dorsal nerve cords and four types of polarized synapses between neurites. Different types of neurons in the CNS could not be distinguished on ultrastructural level due to high similarity in their fine structure. Shared polarized synapses with high electron density of presynaptic components are numerous in the neuropile and nerve cords of this larva. Within the larval body, we detected specialized “support” processes that relate to different tissues. Some “support” processes are also closely related to the nervous system of C. parvicaudata , where they are considered as glia‐like structures. In this case, the fine structure of glia‐like “support” cells of C. parvicaudata differs from those described as glia‐like cells in adult flatworms. We suggest a wide prevalence of glia‐like cells among cercariae, as well as the fact that glia‐like structures in digenean nervous systems can develop from various nonneuronal tissues.
AB - The biology of free‐living and parasitic Platyhelminthes is diverse. Taking into account the widespread prevalence of parasitic flatworms, Digenea is the least studied group regarding the fine structure of nervous system especially of the cercarial life stage. Here, we present a description of the fine structure of central nervous system (CNS) and two types of uniciliate sensory papillae of xiphidiocercaria Cercaria parvicaudata (Microphalloidea, Renicolidae). The present study documents that C. parvicaudata has a complex nervous system that includes a well‐developed ganglion with a cortex of perikarya and glia‐like sheaths, myelin‐like structures within one of the dorsal nerve cords and four types of polarized synapses between neurites. Different types of neurons in the CNS could not be distinguished on ultrastructural level due to high similarity in their fine structure. Shared polarized synapses with high electron density of presynaptic components are numerous in the neuropile and nerve cords of this larva. Within the larval body, we detected specialized “support” processes that relate to different tissues. Some “support” processes are also closely related to the nervous system of C. parvicaudata , where they are considered as glia‐like structures. In this case, the fine structure of glia‐like “support” cells of C. parvicaudata differs from those described as glia‐like cells in adult flatworms. We suggest a wide prevalence of glia‐like cells among cercariae, as well as the fact that glia‐like structures in digenean nervous systems can develop from various nonneuronal tissues.
KW - central nervous system
KW - glia‐like cells
KW - Microphalloidea
KW - sensory papillae
KW - synapses
KW - microphalloidea
KW - glia-like cells
KW - CEREBRAL GANGLION
KW - CELLS
KW - FASCIOLA-HEPATICA
KW - FLATWORMS
KW - SENSORY RECEPTORS
KW - ORGANIZATION
KW - LIVER FLUKE
KW - ULTRASTRUCTURE
KW - BRAIN
KW - PLATYHELMINTHES
UR - https://onlinelibrary.wiley.com/doi/abs/10.1002/jmor.21137
UR - http://www.scopus.com/inward/record.url?scp=85085137023&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/742a4c92-a90f-3ebd-b371-497290147670/
U2 - 10.1002/jmor.21137
DO - 10.1002/jmor.21137
M3 - Article
VL - 281
SP - 765
EP - 777
JO - Journal of Morphology
JF - Journal of Morphology
SN - 0362-2525
IS - 7
M1 - 21137
ER -
ID: 53641046