Glycohistochemical study of the toadfish Halobatrachus didactylus (Scheider, 1801) stomach

Toadfish Halobatrachus didactylus gastric mucosa was studied using conventional and lectin histochemistry. Conventional histochernistry revealed neutral glycoconjugates predominating over acidic ones in the apical zone of both surface epithelial cells and pit cells. The neck cells contained a few neutral glycoconjugates, whereas gastric glands were negative to PAS and AB staining. Lectin histochernistry showed different oligosaccharide expression along the columnar cells. The sub-nuclear cytoplasm was stained with RCA(120), SBA, HPA, GSA I-B-4, GSA II, UEA I, LTA, Con A, KOH-sialidase-WGA. The Golgi zone reacted with RCA(120), D8A SBA, HPA, KOH-sialidase-WGA GSA I-B-4, GSA II, UEA 1, LTA, MAL II, SNA, and showed an increase in DBT staining after KOH-sialidase treatment. The granules of the apical zone stained with PNA, UEA 1, LTA and showed increased PNA reactivity after KOH-sialidase treatment. The luminal Cell coat reacted with PNA, HPA, Con A. KOH-sialidase-WGA, UEA 1, LTA, MAL 11, SNA and KOH-sialidase-PNA. Pit cells showed a minor expression of lectin-binding sites with respect to Columnar cells. Neck cells linked UEA I and LTA and gastric glands reacted with PNA, DBA, SBA, HPA, Con A, GSA I-B-4. KOH-sialidase-WGA and KOH-sialidase-DBA. The results suggest that the stomach of the toadfish H. didact-011s is char, ctcrised by a species-specific glycoconjugate pattern.