Preprint volume - SIBM

Pre-print Volume –Posters
Topic 4: THE ELASMOBRANCHS
gastric pits: scattered open-type neuroendocrine ciliated cells were found in the neck
zone and mucous-secreting cells were identified in the basal gastric pits. All controls
for antibody specificity generated negative results. Further, no leptin-like ir was
detected in the nervous elements. Western Blot analysis showed a single
immunoreactive band of 16±1 kDa (mean±SD) only in the stomach homogenate.
Conclusions - Here we reported for the first time the presence of LEP-like ir in the gut
of S. canicula. Western Blot analysis showed ir with a band close to 16 kDa in the
small-spotted catshark stomach, in according to previously reports on LEP in bony fish
(Gambardella et al., in press). Immunohistochemical results confirm Western Blot
analysis, showing a specific localization of LEP in the gastric portion. Thus stomach,
and in particular gastric mucosa, may be considered the common location for LEP
production in non mammalian vertebrates, as reported by multiple authors (Muruzàbal
et al., 2002), even if further investigations are required to support this hypothesis.
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