A Guide to the Russian Academy of Sciences - University of Texas ...

physiological investigation of the visual system in marine animals. It has been
shown that after migration from the sea to fresh water during the spawning run,
the systems of ionic and osmotic regulation of pink salmon preserve, with a high
degree of stability, the main constants of the water-salt balance in the blood
serum and internal fluids. During the spawning migration the large cells and small
cells in the preoptic nuclei of the pink salmon hypothalamus show two periods of
pronounced functional activity: one after passage from the sea to river and the other
before spawning. The first activation period is connected with the change of habitat
and intensification of sexual maturation and the second is connected with
"spawning stress" and the completion of maturation. During starvation exogenous
insulin activates enzymes of utilization of endogenous glucose in fish. It has been
established that exogenous salmon gonadotropin considerably activates the gonad
growth in immature young chum salmon. In collaboration with the Institute of
Especially Pure Biopreparations (St. Petersburg), prolactin has been, for the first
time, isolated from pink salmon, purified and tested. Special attention has been
given to investigation of the visual system and visually guided behavior in fish. A
new phenomenon in the physiology of fish visual analyzer, change of the eye
cornea coloration in relation to light conditions, has been discovered and described.
In comparative aspect, a scheme of the structure of nerve centers of the brain in
arthropods has been developed and morpho-physiological organization of the
peripheral part of the visual system of decapod crustaceans from the Sea of Japan
has been studied. A complex study is being conducted of the correlations between
the fine morphology of fish retinal neurones and their functional properties.
14. LABORATORY OF COMPARATIVE CYTOLOGY
HEAD Igor Iurii DOLMATOV, Cand. Sci. Biol.
STAFF numbers 10, including 5 Cand. Sci.
RESEARCH OBJECTIVES: Study of cellular mechanisms of the regeneration and
growth processes, their dynamics and regulation in the somatic tissues of marine
invertebrates in relation to life cycles, ecology and taxonomy. A new approach to
the study of the processes of physiological and reparative regeneration, cell
proliferation and differentiation in the marine invertebrate tissues has been
developed in the course of many-year research under the leadership of Dr. N. L.
Leibson. Among various taxa, species and natural states have been found as well as
experimental models (holothurians) developed which are promising for analysis of
the mechanisms and cell sources of regeneration. Some renewing systems have
described for mollusks and echinoderms. Most of the intestinal epithelia of the
animals have diffuse cell reproduction and are devoid of topographically separated
cambial zones. The evolutionary significance of this initial organization of the
epithelial layer is substantiated. Dr. Le terocoelodermal tissue type) in holothurians
and, probably, some other animals. Annual cyclic changes in the physiological
regeneration and deep structural reorganizations of the tissues have been
discovered. The seasonal dynamics of proliferation in a number of mollusks and
echinoderms have been studied for the first time for marine invertebrate tissues.
Studies have begun on the use of marine invertebrate tissues as promising sources
and targets (test objects) of growth factors and some possible agents for the
medicinal purposes.
15. LABORATORY OF COMPARATIVE BIOCHEMISTRY
HEAD Vasily I. SVETASHEV, Cand. Sci. Chem.
STAFF numbers 18, including 1 Dr. Sci., 7 Cand. Sci.
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