Cells showing immunoreactivity for calcitonin or calcitonin gene-related peptide (CGRP) in the central nervous system of some invertebrates.
In the central nervous system of some species of several invertebrate phyla, including land planarians (Platyhelminthes), ribbon worms (Nemertina), slugs (Mollusca), polychaetes, earthworms and leeches (Annelida), pill bugs (Arthropoda), and beard worms (Pogonophora), salmon calcitonin-immunoreactive cells and rat calcitonin gene-related peptide (CGRP)-immunoreactive cells were found by immunohistochemistry. These immunoreactive cells were located in the region surrounding the neuropile, although the sizes of the cells varied according to species. Some of them were round or polygonal and regarded as apolar nerve cells because of their lack of cytoplasmic processes, whereas others were spindle-shaped or elongated, being comparable with unipolar nerve cells because of extension of their cytoplasmic processes in the direction of the neuropile. In some cases, it was noted that the cytoplasmic processes had complicated branches or formed loop-like structures at their ends. These observations suggest that a calcitonin-like or CGRP-like substance is extensively present in invertebrates as well as vertebrates.
Sasayama
Y
Y
Department of Biology, Faculty of Science, Toyama University, Japan.
Katoh
A
A
Oguro
C
C
Kambegawa
A
A
Yoshizawa
H
H
D000818:Animals; D005075:Biological Evolution; D002116:Calcitonin / Q000032:analysis*; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis*; D002490:Central Nervous System / Q000378:metabolism; D007124:Immunoenzyme Techniques; D007448:Invertebrates / Q000378:metabolism*
D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide