Immunoreactivity of the corpuscles of Stannius of the garpike, Lepisosteus osseus , to antisera against salmon and trout stanniocalcins

Abstract

Abstract. Stanniocalcin-immunoreactive cells were local ized in the corpuscles of Stannius of a holostean fish, the garpike (Lepisosteus osseus), using antisera against salmon and trout stanniocalcins and the peroxidase-antiperoxidase and protein A-gold immunohistochemical methods. The stanniocalcin-immunoreactive cells were periodic acid-Schiff-positive, and antibody staining was abolished if the antiserum was preabsorbed with corpus cle homogenate. Immunocytochemistry revealed two re active cell types in the glandular parenchyma, and im munoreactivity was confined to the secretory granules. Staining of the granules was also abolished when the antisera were blocked with crude corpuscle homogenate. When corpuscle extracts from garpike were subjected to sodium dodecyl sulphate-polyacrylamide gel elec trophoresis and Western blot analysis, a single dense band was evident with a molecular weight of ^68 kDa under non-reducing conditions, whereas three bands were observed (^29, -31, and ^3 4 kDa) under reduc ing conditions. Staining of all bands disappeared follow ing preabsorption of the antiserum with salmon stanniocalcin, trout stanniocalcin, or garpike corpuscle extract. The results are compared with stanniocalcins from an other extant holostean, the bowfin (Amia calva), and from more modern bony fishes, the teleosts.

Stanniocalcin from an ancient teleost: a monomeric form of the hormone and a possible extracorpuscular distribution

“…In adjacent sections, cells immunoreactive to the probing antibody (Fig. 1b) were closely correlated with those cytoplasmic areas stained by the PAS technique and the results were similar to those previously described (Marra et al, 1992(Marra et al, , 1994(Marra et al, , 1995. Immunoreactivity of the cells confirms the corpuscles as the CS.…”