[The direct activating effect of a nonapeptide neurohormone (vasotocin) on the thyroid and interrenal glands of sturgeons in in-vitro experiments].

An in-vitro effect of nonapeptide neurohormone vasotocin on thyroid and interrenal glands was studied in hybrid of Siberian and Lena sturgeons [correction of salmons] at light microscopy level using morphometric method. At a concentration of 0.1 and 1 nmol/l vasotocin was shown to exert undirectional stimulating effect on the thyroid and interrenal gland functions.

[The effect of factors of the supraoptic and paraventricular hypothalamic nuclei on the growth, cellular reproduction and cytodifferentiation of the adenohypophyseal epithelium].

In hypophysectomised noninbred [correction of inbred] rats and in male rabbits, a direct influence of stimulation with oxytocin, vasopressin, dopamine of the hypophysis substance's adenocytes enhanced their proliferation as well as the DNA synthesis. The role of hypothalamic nonapeptides as the regulators of cells and tissues homeostasis is discussed.

The hypothalamo-hypophyseal system in Acipenseridae. XI. Morphological and immunohistochemical analysis of nonapeptidergic and corticoliberin-immunoreactive elements in hypophysectomized sterlet (Acipenser ruthenus L.).

The regeneration of the hypothalamo-hypophyseal system (HHS) has been studied in the sterlet following hypophysectomy (HypoX). Significant portions of nonapeptide and corticoliberinergic (CRH) neurosecretory cells (NSCs) underwent degeneration. Surviving NSCs had a great regenerative ability; damaged axons formed anew, uncharacteristicly for intact fishes, axovasal and axoventricular contacts.

[The morphofunctional specialization of the main and accessory magnocellular neuroendocrine nuclei of the hypothalamus].

Intensity of vasopressin gene expression was compared in neurosecretory cells of supraoptic, postoptic, paraventricular and 6 accessory nuclei (extrahypothalamic included) of adult intact Wistar rats to study the morphofunctional specialization of magnocellular hypothalamic nuclei. Messenger RNA (mRNA) was revealed by radioautographic in situ hybridization, using 35S labelled exonic-intronic probe. By densitometry the amount of label was shown not to differ significantly in neurosecretory cells of all nuclei studied.

[A morphofunctional analysis of the nuclear apparatus of the nonapeptidergic neurosecretory cells in the vertebrate hypothalamus].

A vast comparative material obtained on fishes, amphibians and mammals has been analysed using ecological and experimental histophysiological approaches. The structural organization of the nuclear apparatus of nonapeptidergic neurosecretory cells, especially in the lower vertebrates has been clearly shown to differ from that of the classic neurones. Morphometrical characteristics of nonapeptidergic neurosecretory cells of hypothalamic centers can be used for a reliable evaluation of their functional conditions.

[Nontraditional "large-cell" neuroendocrine formations (accessory nuclei) in the brain of Anamnia and Amniota].

Using immunochemical PAP-method nonapeptidergic neuroendocrine formations in the hypothalamus and adjacent brain areas of fishes (the sterlet Acipenser ruthenus, the shark Scylliorhinus canicula), amphibians (the frog Rana temporaria), reptiles (the snake Natrix natrix), mammals (rats and dogs) and human have been studied. In Amniota and human accessory nuclei (AN) in addition to main "magnocellular" nuclei (supraoptic, postoptic and paraventricular) were discovered. Two AN, circular and dorsolateral ones, were found in snakes, and circular, dorsolateral, forniceal and extrahypothalamic AN were revealed in rat, dog and human brain.

[A morphofunctional study of the hypothalamic postoptic nucleus after hypophysectomy, cooling and immobilization in rats].

Response of the vasopressin (VP) and oxytocin (OT) cells of hypothalamic post optical nucleus (PON) was studied in male Wistar rats under various experimental conditions. Seven days after hypophysectomy, the majority of both VP- and OT-cells became pyknomorphic which seemed to be the result of transsection of the PON-cell axons and indicated that the PON-cells released neurohormones from the posterior pituitary into the blood. When rats were cooled (2 h at 4 degrees C), the size of nucleoli in VP-cells diminished significantly, but in rats stressed by severe immobilization (20 min) these cells revealed clear signs of activation.

[The reaction of the nonapeptidergic neurosecretory cells of the hypothalamic accessory groups to cold and immobilization stresses in rats].

Male Wistar rats were subjected to stresses of two different kinds: cooling (2 h at 4 degrees C) or immobilization (20 min). In the rat hypothalamus, oxytocinergic (OTE) and vasopressinergic (VPE) cells were studied immunohistochemically (PAP-method) in following magnocellular accessory groups: circular (CG), perifornical (PFG), ventrolateral (VLG), dorsolateral (DLG), extrahypothalamic (EHG), and periventricularly localized OTE cells (PVC). In cooled rats, sizes of cellular nucleoli increased significantly in both OTE and VPE cells of the CG, EHG and PVC indicating activation of hormone production.

The primary structure of sturgeon prolactin: phylogenetic implication.

The complete amino acid sequence of prolactin (PRL) from a chondrostean species, the sturgeon (Acipenser gueldenstaedti), has been determined. Sturgeon PRL was isolated from the pituitary glands by gel filtration on a Sephadex G-25 column and high-performance liquid chromatography on a reverse-phase column following acid-acetone extraction. Sturgeon PRL was identified by immunoblot reactivity using antisera against salmon and ovine PRL.

[The detection of corticoliberin in the neurosecretory cells of additional Gomori-positive centers in the rat hypothalamus].

The experiments were carried out in male Wistar rats in which deafferentation of the mediobasal hypothalamus was performed or colchicine (75 micrograms/10 microliters of saline) was inoculated into the III ventricle cavity. Using the PAP-method, the presence of corticoloberin was determined immunohistochemically in neurosecretory cells of additional groups (AG) of the hypothalamus: circular, perifornical (PFG), dorsolateral, ventrolateral, as well as extrahypothalamically located group (the internal capsule area). The intact rats were shown to have no corticoliberin-immunoreactive (CL-IR) cells in any of AG.

Ultrastructural radioautographic analysis of neurogenesis in the hypothalamus of the adult frog, Rana temporaria, with special reference to physiological regeneration of the preoptic nucleus. II. Types of neuronal cells produced.

Light- and electron-microscopic radioautography was used to identify the newly formed neuronal cells in the hypothalamic preoptic area of the frog. Adult Rana temporaria that had been caught in May/June received repeated 3H-thymidine injections and were sacrificed 30 days later. Heavily labeled cells were found in 1-micron plastic coronal sections of the preoptic area and then analysed in electron-microscopic radioautographs of neighbouring thin sections.

Ultrastructural radioautographic analysis of neurogenesis in the hypothalamus of the adult frog, Rana temporaria, with special reference to physiological regeneration of the preoptic nucleus. I. Ventricular zone cell proliferation.

The localization and fine structure of proliferating cells in the hypothalamic preoptic area were studied by light- and electron-microscopic radioautography 1-2 h following single application of 3H-thymidine to adult Rana temporaria taken from their natural habitat in the spring and autumn. 3H-thymidine uptake by proliferating cells was much more pronounced in frogs caught in May/June, i.e.

[The blocking effect of adrenaline on the thyroid-stimulating effect of vasopressin in rats].

Effect of various doses of oxytocin, vasopressin or adrenalin on the thyroid gland activity was studied in hypophysectomized and nonoperated rats 20 minutes after a single injection of the neurohormones. The minimal applied dose of the neurohormones stimulated increasing of their concentration in blood up to level typical for stress reaction. Injection of oxytocin led to no effect at any dose.

[The significance of feedback in accomplishing the rat hypothalamic nonapeptidergic center reaction to short-term immobilization stress].

Stress response of oxytocin- and vasopressinergic cells in the supraoptic and paraventricular centers of the hypothalamus was studied morphometrically in rats with intact hypophysis and 7 days after hypophysectomy. Severe immobilization (for 20 min.) was applied as an unspecific short-term stress.

[The effect of vasotocin and mesotocin on the suprarenal gland of the frog Rana temporaria in vivo and in vitro].

Biochemical and morphometric analyses have been made of the effects of nonapeptide neurohormones, vasotocin and mesotocin, on the chromaffin tissue of the adrenal gland of the frog, both in vivo and in vitro experiments. It was shown that vasotocin exerts stimulating effect on the suprarenal gland whereas mesotocin inhibits the latter. In vitro experiments revealed that adrenalin may abolish the effect of nonapeptides on the suprarenal gland.