Peptides related to insulin-like growth factor 1 in the gastro-entero-pancreatic system of bony and cartilaginous fish.
Evidence for the presence of peptides, related to insulin-like growth factor 1 (IGF-1) has been obtained in serum and various organs of representatives of osteichthyes and chondrichthyes, i.e., the bony fish Myoxocephalus (Cottus) scorpius and the cartilaginous fish Raja clavata. The peptides were identified by means of gel chromatography and an IGF-1 radioimmunoassay. IGF-1-like immunoreactivity was detected in three different apparent molecular mass forms, i.e., 17 kDa, 6 kDa and 4 kDa, the occurrence of which seemed to depend on the species. When the same antiserum was used immunohistochemically, IGF-1-like immunoreactivity was observed in endocrine cells of the open type in the intestinal mucosal epithelium. These cells exhibited distinct and species-specific distribution patterns. Endocrine cells of the pancreas as well as epithelial cells of the pancreatic duct also showed IGF-1-like immunoreactivity. Occasionally, IGF-1-like immunoreactivity was observed also in interstitial cells. The distribution patterns and densities of the IGF-like immunoreactive cells correlated with the results obtained by radioimmunoassay of the crude extracts. Absorption studies indicated that the IGF-1-like peptides observed differ from mammalian and submammalian insulins as well as from mammalian IGF-1.
Reinecke
M
M
Department of Neuroendocrinology, University of Zürich, Switzerland.
Drakenberg
K
K
Falkmer
S
S
Sara
V R
VR
D000818:Animals; D005075:Biological Evolution; D002851:Chromatography, High Pressure Liquid; D004064:Digestive System / Q000737:chemistry*; D004702:Endocrine Glands / Q000737:chemistry; D005399:Fishes / Q000378:metabolism*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D011863:Radioimmunoassay
D007334:Insulin-Like Growth Factor I