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PubMedDate not supplied

[Mechanism of metabolic adaptation].

The paper presents results of investigations on some mechanisms of metabolic adaptation in mammals. There are four sections in the tissue metabolic system of acid-base homeostasis: polyamines as factors of metabolic adaptation; significance of carbon dioxide for metabolic response formation in hypobiosis; polyamines metabolism in hypobiosis. Peculiarities of intermediate metabolism have been analyzed in animal tissues under the changes in H+, CO2 and HCO3- concentrations. Basing on a new interpretation of the experimental data and detected regularity in the metabolism, conclusion on the existence of a new acid-base homeostasis system in the tissues has been made. The results of polyamines metabolism investigations in the mammals under the stress have been described. The experimental data make us to believe that changes in polyamines synthesis and ODC activity in particular, is a part of stereotype nonspecific response to any stress impacts and one of the factors of cell metabolic adaptation. Some new data on mechanisms of formation and control of metabolic status of animals in the natural and artificial hibernation have been presented. The key idea is that in the state of hypobiosis the carbon dioxide (HCO3-) appears as a regulatory factor of metabolic adaptation, which is able to realize its action directly via affecting numerous biochemical events. The participation of polyamines in adaptive metabolic response to hybernation factors is suggested. Some peculiarities of ornithine decarboxilase and transglutaminase activity during the different stages of genuine and artificial hypobiosis have been demonstrated.

Acid-Base Equilibrium↗
PubMed1977

Environmental influence on ovulation and embryonic development in Rana pipiens.

Environmental effects on ovulation and embryogenesis in Rana pipiens were assessed using both freshly-captured fall animals and laboratory-conditioned females which had undergone vitellogenesis in the laboratory. Frogs in both categories were divided into two groups. Ovulation was hormonally induced in one group of females prior to cold exposure and in the second group of animals following an 8-week-period at 4 degrees C with an 8L 16D photoperiod. The incidence of both ovulation and normal embryonic development was increased following exposure of the animals to low temperatures and short daylength. Those animals which only partially ovulated prior to cold treatment did not respond to hormone injections following the period of cold exposure. Examination of the ovaries of these females revealed a much greater degree of oocyte resorption than was found in frogs whose initial ovulation was induced only after exposure to cold temperatures. The administration of ovulation-inducing hormones prior to artificial hibernation may thus have initiated a phase of oocyte resorption which progressed even at 4 degrees C. The incidence of ovulation was similar in wild-caught and laboratory-conditioned females, but eggs from the latter showed a much lower percentage of development to Shumway stage 20. This effect may have been related to differences in the environmental factors to whcih the two groups were exposed during oogenesis.

Animals↗
PubMed1989

Spontaneous maturation of follicular oocytes in Rana dybowskii in vitro: seasonal influences, progesterone production and involvement of cAMP.

Seasonal and hormonal influences regulating oocyte maturation (germinal vesicle breakdown, GVBD) in ovarian follicles of Rana dybowskii were investigated. During the early winter (Dec.-Jan.) GVBD occurred at a low incidence following in vitro culture of intact follicles. Addition of progesterone of frog pituitary homogenate (FPH) to such follicles induced oocyte maturation, whereas IBMX or forskolin inhibited hormone-induced oocyte maturation. The time course of spontaneous in vitro maturation varied markedly with the seasons and between animals. Follicles isolated from the ovaries in early February required 21-24 hours of culture to mature spontaneously, and addition of FPH or progesterone to the culture medium markedly accelerated the time course of GVBD. In contrast, follicles isolated in late February matured very rapidly (less than 6 hours), and FPH or progesterone were ineffective in accelerating the time course of GVBD. IBMX and forskolin separately or in combination stimulated follicular progesterone production, which resembled that seen following FPH stimulation. FPH addition to such follicles shifted the steroid peak to the left (accelerated) and increased the absolute amount of hormone detected in late-maturing follicles (50% GVBD, about 18 hours) but not in rapidly maturing follicles (50% GVBD, 3 hours). In contrast to other amphibians, a high incidence of spontaneous oocyte maturation occurred during in vitro culture. Essentially all animals exhibited spontaneous maturation during the normal breeding season, even those animals collected in the early winter and kept in artificial hibernation at 4 degrees C for extended periods.

Animals↗
PubMed1986

Vitellogenesis in the lizard Lacerta vivipara jacquin. II. Vitellogenin synthesis during the reproductive cycle and its control by ovarian steroids.

An analysis of the development of the vitellogenic process following artificial hibernation in the lizard Lacerta vivipara was undertaken. For that purpose, organ weights (ovaries, oviducts, liver, fat bodies) and plasma concentrations of total proteins, calcium, and estrogens were monitored. The induction of the vitellogenic growth of 2-5 oocytes per ovary was characterized by a rapid increase in calcemia (from 2.4-2.6 mM to 4-10 mM), and in oviduct and liver weights. During the active and continuous phase of vitellus incorporation (congruent to 3 weeks, follicle diameter 1.6-2.0 mm to greater than 5 mm) the developments of ovaries and oviducts were positively correlated, liver weight and calcemia remained elevated (respectively, 1.2-2.2 times and 2.5-3.5 times the previtellogenic values). Ovulation was preceded by a significant rise in calcemia and followed by a decrease in liver weight, but no modification of oviduct mass. Plasma concentration in total proteins (50-60 mg/ml) was not modified during the entire process. Plasma estrogens were difficult to measure in this small species. Levels of estradiol-17 beta were very often below the assay sensitivity (less than 0.3-0.6 ng/ml), never above 2 ng/ml, and very variable among individuals. No correlation with vitellogenin production could be established. Therefore, the abilities of different ovarian steroids to induce vitellogenin synthesis were tested in vivo. To reduce the rise of plasma estradiol titer (observed during a 4-week experiment), the steroids were implanted in ovariectomized lizards for a short time (5 days). The vitellogenic response was assessed by measuring the distribution of the 32P radioactivity between the acidoprecipitable plasma fraction and the plasma vitellogenin recognized by the lizard antivitellogenin serum. Plasma titers of estradiol-17 beta were monitored. The estrone potencies could not be determined as this treatment involved an important rise in estradiol level. Progesterone, delta 4, testosterone, and 5 alpha-androstanediol were unable to stimulate vitellogenin synthesis. Estradiol-17 beta was the only effective steroid. It was further demonstrated that the estradiol-induced hypercalcemia, hyperproteinemia, and liver growth in ovariectomized lizards were dependent upon the total amount of estrogen injected.

Androstane-3,17-diol↗
PubMedDate not supplied

History of the discovery and clinical introduction of chlorpromazine.

BACKGROUND: The historical process of discovery and clinical introduction of chlorpromazine, one of the greatest advances of 20th century medicine and history of psychiatry, is analyzed. METHODS: In this review, we have studied the original works of pioneers in the discovery and clinical use of chlorpromazine, as well as the contributions of prestigious researchers (historians, pharmacologists, psychiatrists, etc.) about this topic. RESULTS: The discovery of phenothiazines, the first family of antipsychotic agents has its origin in the development of German dye industry, at the end of the 19th century (Graebe, Liebermann, Bernthsen). Up to 1940 they were employed as antiseptics, antihelminthics and antimalarials (Ehrlich, Schulemann, Gilman). Finally, in the context of research on antihistaminic substances in France after World War II (Bovet, Halpern, Ducrot) the chlorpromazine was synthesized at Rhône-Poulenc Laboratories (Charpentier, Courvoisier, Koetschet) in December 1950. Its introduction in anaesthesiology, in the antishock area (lytic cocktails) and "artificial hibernation" techniques, is reviewed (Laborit), and its further psychiatric clinical introduction in 1952, with initial discrepancies between the Parisian Val-de-Grâce (Laborit, Hamon, Paraire) and Sainte-Anne (Delay, Deniker) hospital groups. The first North-American publications on chlorpromazine took place in 1954 (Lehmann, Winkelman, Bower). The introduction of chlorpromazine in the USA (SKF) was more difficult due to their strong psychoanalytic tradition. The consolidation of the neuroleptic therapy took place in 1955, thanks to a series of scientific events, which confirmed the antipsychotic efficacy of the chlorpromazine. CONCLUSIONS: The discovery of the antipsychotic properties of chlorpromazine in the 1950s was a fundamental event for the practice of psychiatry and for the genesis of the so-called "psychopharmacological revolution."

Antipsychotic Agents↗
PubMed1988

The influence of hibernation on the interferon response in the spotted suslik (Spermophilus suslicus).

According to the season, the environmental temperature, and their physiological state (whether active or in hibernation), spotted susliks produce different amounts of interferon (IFN) in response to intraperitoneal induction with Newcastle disease virus (NDV). Even though injection of NDV aroused hibernating animals, susliks treated during deep winter hibernation or artificial summer hibernation, or when aroused from winter hibernation, had significantly less IFN in their serum and organs than animals active in summer. Minced tissues taken from such animals and infected with NDV in vitro produced similar relative amounts of IFN. The effects of other environmental factors were studied: IFN production in vivo was increased by a high concentration of CO2 (5%) in the air, but decreased by electric shock stress. A hyporeactive response to IFN induction in vivo was produced in active susliks but not in animals hibernating in summer. These changes in the IFN system associated with season and physiological state cannot be explained merely in terms of the effect of differences in body temperature; they involve also adaptive changes in the animal associated with the onset of hibernation.

Animals↗