Synaptic dimorphism in Onychophoran cephalic ganglia

 

Đã lưu trong:
Chi tiết về thư mục
Nhiều tác giả: Peña Contreras, Z., Mendoza Briceño, R.V., Miranda Contreras, L., Palacios Prü, E.L
Định dạng: artículo original
Trạng thái:Versión publicada
Ngày xuất bản:2007
Miêu tả:The taxonomic location of the Onychophora has been controversial because of their phenotypic and genotypic characteristics, related to both annelids and arthropods. We analyzed the ultrastructure of the neurons and their synapses in the cephalic ganglion of a poorly known invertebrate, the velvet worm Peripatus sedgwicki, from the mountainous region of El Valle, Mérida, Venezuela. Cephalic ganglia were dissected, fixed and processed for transmission electron microscopy. The animal has a high degree of neurobiological development, as evidenced by the presence of asymmetric (excitatory) and symmetric (inhibitory) synapses, as well as the existence of glial cell processes in a wide neuropile zone. The postsynaptic terminals were seen to contain subsynaptic cisterns formed by membranes of smooth endoplasmic reticulum beneath the postsynaptic density, whereas the presynaptic terminal showed numerous electron transparent synaptic vesicles. From the neurophylogenetic perspectives, the ultrastructural characteristics of the central nervous tissue of the Onychophora show important evolutionary acquirements, such as the presence of both excitatory and inhibitory synapses, indicating functional synaptic transmission, and the appearance of mature glial cells.
Quốc gia:Portal de Revistas UCR
Tổ chức giáo dục:Universidad de Costa Rica
Repositorio:Portal de Revistas UCR
Ngôn ngữ:Inglés
OAI Identifier:oai:archivo.portal.ucr.ac.cr:article/6078
Truy cập trực tuyến:https://archivo.revistas.ucr.ac.cr/index.php/rbt/article/view/6078
Từ khóa:Onicóforo
sinapsis
Peripatus
ultraestructura
ganglio cefálico
evolución
Onychophora
synapses
ultrastructure
cephalic ganglia
evolution