The development of method of hormonal stimulation of N.L.Gerbilsky and appearance of contemporary preparations of long-term storage

The The main discovery of the 20th century in the field of fish breeding is hormonal stimulation of final stages of maturation of fish at hatcheries. The «father» of method of pituitary injections was Leningrad ichthyologist N.L. Gerbilsky. The main achievements of N.L. Gerbilsky and his school are methods of mass extraction of fish pituitaries, their dehydration by acetone for later storage and use, testing of pituitary gonadotropic activity on different objects. The induction of ovulation in female loaches Misgurnus fossilis or spermiation reaction of Galli-Mainini in male frogs Rana ridibunda or R. temporaria were used for pituitary testing. The effective doses of dried pituitaries for sturgeons were determined in milligrams and loach units or frog units. The method of pituitary injections was used for functioning of sturgeon breeding facilities at Volga, Don, Kuban and Kura and other rivers. For guaranteed answer fish breeders used hyperdoses of dry pituitary powder because its gonadotropic activity varied in dependence on stage of maturity of fish-“donors”. The followers of N.L. Gerbilsky led by Prof. I.A. Barannikova developed the technique of production of special glycerol pituitary extract (GPE) with determined gonadotropic activity. The main role in formulation of the recipe of GPE belongs to A.A. Boyev. The use of GPE has removed the problem of hyperdosing leading to worsening quality of mature germinal cells of sturgeons. Later, A.A. Boyev on the basis of this recipe with replacement of glycerol to propylene glycol created stabilizing solution of analogue of mammal LH-RH (“surphagon”) of long-term storage with concentration of active substance from 20 to 500 micrograms/ml.

Renotropic and gonadotropic activity in homologous and heterologous hybrids of ovine luteinizing hormone and human chorionic gonadotropin subunits

We previously demonstrated the renotropic activity of ovine and porcine LH, i.e. the stimulation of [3H]thymidine incorporation into the renal DNA of castrated hypophysectomized rats. We conducted this study to determine which condition is required to promote renotropic activity. We prepared homologous (oLHα· oLHβ, hCGα·hCGβ) and heterologous (oLHα·hCGβ, hCGα·oLHβ) hybrids from isolated oLH- and/or hCG-derived subunits. Native oLH and all hybrids showed gonadotropic activity when examined for cyclic AMP generation in cultured Leydig tumour cells (MA-10). Native oLH and the hybrids which showed renotropic activity were all found to contain at least one of the oLH subunits. Our findings point out the important, special role of oLH subunits in promoting renotropic activity. The condition required is suggested to be presence of a common structure in the two oLH subunits. Such a structure should consequently not be present in hCG. A carbohydrate moiety of oLH containing a sulphate group is proposed as a candidate, but the assumption remains to be demonstrated.

Histochemical and biochemical changes in the ovary during sexual maturity of the soft-shelled turtle, Lissemys punctata punctata Bonnoterre

Changes in some histochemical and biochemical aspects of the ovary between juvenile and adult (breeding) soft-shelled turtles, Lissemys punctata punctata have been studied. 3 ss-hydroxysteroid dehydrogenase activity in the ovary was higher in adults than in juveniles. While cholesterol and ascorbic acid levels decreased, concentrations of sialic acid, glycogen, DNA and RNA with the phosphatases (both acid and alkaline) activities increased significantly in adults from those of juveniles. It is suggested that alterations in the above parameters are related to ovarian steroidogenesis as well as to gonadotropic activity.