[Purification and ligand-receptor analysis of insulin-related peptides from pedal ganglion of the mollusc Anodonta cygnea]. / Ochistka i ligand-retseptornyi analiz insulinopodobnykh peptidov pedal'nogo gandliia molliuska Anodonta cygnea.

Six insulin-related peptides (IRPs) from pedal ganglions of the molluscs Anodonta cygnea have been isolated and purified by reverse-phase chromatography. Each peptide (designated as IRP8-IRP13) showed its own retention time on the HPLC column. The testing of IRPs in radioreceptor systems specific for insulin and insulin growth factor-I (IGF-I) showed their ability to bind to both types of receptors. The concentration of IRPs, producing a 50% inhibition of porcine 125I-insulin binding with rat liver plasma membrane receptors (IC50) for IRP 10, was 1167 nM, IRP11--833 nM, IRP13--1333 nm. IRP8, IRP9, IRP12 in the maximum concentration of 10(4) ng/ml displaced less than 50% of labeled hormone. All of the six peptides were capable of competing with human 125I-IGF-I for binding to receptors of a fraction of rat brain membranes. IRP8, IRP9 and IRP12 had close means equal to 1167 nM, 1500 nM, 1167 nM, respectively. Another group including IRP10, IRP11 and IRP13 showed a much higher activity (833, 83 and 500 nM, respectively). The results obtained from radioligand analysis revealed the predominance of IGF-I binding properties in all peptides of pedal ganglions. At the same time, apparent proximity of IRP's physico-chemical characteristics to porcine insulin, and also the revealed dose-dependent binding to both insulin and IGF-I receptors suggest a bifunctionality of mollusc peptides. The expression level of this bifunctionality may be associated with the molecular structure pecularities of individual isoforms.

[The growth-stimulating activity of the insulins from teleosts]. / Roststimuliruiushchaia aktivnost' insulinov kostnykh ryb.

Growth-stimulating properties of insulins from cyclostomes, teleosts and mammals were evaluated by their capacity to promote the uptake of [35S]-sulfate by fish branchial cartilages. It was shown that all the tested hormones exhibit promotor properties increasing the uptake of labeled sulfate by 1.5-3 times. The effects depend both on the dose of the hormone and on peculiarities of its molecular structure.

[The mitogenic effect of insulin isolated from the mammalian brain on Swiss 3T3 cells]. / Mitogennoe vliianie insulina, vydelennogo iz mozga mlekopitaiushchikh, na kletki Swiss 3T3.

Mitogenic properties of the insulin derived from pig brain were compared with the action of pancreatic (standard) pig insulin and epidermal growth factor (EGF) using the culture of Swiss 3T3 cells. The brain insulin, likely as the pancreatic insulin, induced uptake of 14C-thymidine by resting cells in a dose-dependent manner at concentration of 0.5-2.0 micrograms/ml in culture medium. However, at equal concentrations of these hormones the proliferating effect of the brain insulin appeared to be 2-fold higher than the effect of the pancreatic hormone. At the same time the mitogenic action of both hormones was lower than that of EGF (10 ng/ml). The additive effect of the brain insulin and EGF, administered in combination, was more pronounced than the effect of the pancreatic insulin combined with EGF. The data obtained suggest a possible participation of brain insulin in the process of nerve cell proliferation.

[Amino acid sequence of the insulin of the dog salmon Oncorhynchus keta]. / Aminokislotnaia posledovatel'nost' insulina kety Oncorhynchus keta.

It has been demonstrated that A-chain of insulin in the salmon O. keta consists of 21 amino acid residues with N-terminal glycine and C-terminal asparagine. B-chain is formed by 29 residues with alanine and lysine as N- and C-terminals correspondingly.

[Comparative study of the immunological properties of insulins and insulin-like substances of vertebrates and invertebrates]. / Sravnitel'noe issledocanie immunologicheskikh svoistv insulinov i insulinopodobnykh veshchestv u pozvonochnykh i bespozvonochnykh.

Comparative studies have been made on immunological properties of insulins (bovine, porcine and fish--Oncorhynchus gorbuscha, O. keta) and insulin-like substances of the mollusk Anodonta cygnea and starfish Asterias rubens in homologous and heterologous for these hormones radio-immune systems. It was concluded that each of these systems reveals in the insulins and insulin-like substances investigated the identical antigenic determinants. At the same time, low affinity of the hormones to heterologous antibodies indicates the existence of significant differences in the structure of binding sites.

[Preparation of an insulin-like substance from molluscs and its antiserum]. / Poluchenie insulinopodobnogo veshchestva molliuskov i antisyvorotki k nemu.

A substance with insulin-like activity was obtained from visceral organs (excluding foot, gills and mantle) of the freshwater bivalve molluscs Unio pictorum and Anodonta cygnea. Injecting this substance to guinea pigs, antiserum was also obtained. Using the obtained antiserum in immunostaining experiments, the cells which produce insulin-like substance were identified in the intestinal epithelium of the midgut in A. cygnea.

[The isolation and purification of insulins from the pink salmon Oncorhynchus gorbuscha and the walleye pollock Theragra chalcogramma]. / Vydelenie i ochistka insulinov gorbushi Oncorhynchus gorbuscha i mintaia Theragra chalcogramma.

Crystalline insulins have been obtained from the insular tissue of the teleosts O. gorbuscha and Th. chalcogramma which is located separately from the exocrine tissue. Some tests to the homogeneity and purity of the preparations obtained were made. Biological activity of insulin as revealed by seizure tests in mice is equal to 20.1 +/- 1.19 IU/mg in O. gorbuscha and 16.9 +/- 1.99 IU/mg in Th. chalcogramma, amounting correspondingly to 83 and 70% of the activity of mammalian standard insulin. The yield of preparations calculated per wet weight of the insular tissue is equal to 2 mg/g in O. gorbuscha and 0.7 mg/g in Th. chalcogramma. It is significantly higher than the yield of mammalian insulins calculated per the weight of the pancreas. This finding may be of some interest with respect to the use of fish as a source of hormonal preparations.

[Corticosteroid concentration in the blood of the Russian sturgeon, Acipenser güldenstädti, at different stages in its life cycle]. / Soderzhanie kortikosteroidov v krovi u russkogo osetra Acipenser güldenstädti na razlichnykh étapakh zhiznennogo tsikla

Corticosteroid content of the blood has been measured during upstream and downstream migrations as well as during sea period of life of the sturgeon A. galdenstädti. It was shown that during anadromous migration before spawing, the level of corticosteroids in the blood increases, the increases beginning already during the sea period. Corticosteroid content of the blood decreases after spawning. The results obtained confirm the histophysiological data.