[Effects of neuropeptide Y on rat body temperature in normal conditions and after ethanol administration]. / Vliianie neiropeptida Y na temperaturu tela krys v norme in na fone vvedeniia étanola.

It was shown that intracerebroventricular (icv) administration of 2 micrograms neuropeptide Y (NPY) increased the rectal temperature in rats 2.5 hours postinjection. During 5 days we analysed dynamics of the effect of NPY on alcohol-induced hypothermia in this particular interval. 2 micrograms of NPY were given daily 30 min prior to 25% solution of ethanol (3 g/kg weight rat) intraperitoneal injection. It was found that NPY can prevent the attenuation of alcohol hypothermia on the 3-d and 4-th injection day. It was supposed that the inhibitory effect of NPY on the development of alcohol tolerance may be due to the capacity of NPY to increase food behavior. So it's known that activation of other competitor motivation may inhibit the development of alcoholism.

Neuropeptide Y and catecholamine-mediated neuronal transmission in mechanisms of feeding-behaviour induction.

Intracerebroventricular administration of various doses of neuropeptide Y (NPY) to rats had different effects on their feeding behaviour: the lowest dose (100 ng) decreased food intake, but higher doses (5 micrograms) markedly increased the intake. Prazosin, a selective blocker of alpha 1-adrenergic receptors, suppressed the effect induced by 5 micrograms (but not 100 ng) NPY. No such effect was observed with injections of yohimbine or propranolol. The opiate receptor antagonist, naloxone, blocked the feeding behaviour induced by 5 micrograms NPY without having any other effects on the responses induced by 100 ng NPY. The data obtained testify to heterogeneity within the NPY receptors of the central nervous system. It is concluded that the effects of high doses of NPY on feeding behaviour are mediated, at least in part, by alpha 1-adrenergic receptors.

[Effects of neuropeptide Y on behavior and noradrenaline level in the brain]. / Vliianie neiropeptida Y na povedenie i dinamiku urovnia noradrenalinav mozge.

The administration of neuropeptide Y in lower doses (1 and 100 ng/rat) into the lateral ventricle of the brain gave rise to the inhibition of locomotor activity, weakening of the orienting-exploratory behaviour, increase in the period of rest in animals. Feeding and drinking behaviour after the administration of neuropeptide was not observed. Alterations of behaviour in rats were followed by a dose-depended increase in noradrenaline in hypothalamus. No changes were observed in the content of noradrenaline in the frontal cortex and septum. Some variations in the level of noradrenaline were found in amygdala and hippocamp. It may be assumed that behavioural effects, aroused by the central administration of neuropeptide Y, is connected with the activation of catecholaminergic systems of hypothalamus.

[Effect of neurohypophyseal peptides on the formation of a conditioned feeding reflex in the rat]. / Vliianie neirogipofizarnykh peptidov na formirovanie uslovnogo pishchevogo refleksa u krys.

The influence of intraperitoneal injection of vasopressin (LVP), oxytocin (OXY) and their fragments (DGAVP, PLG) on the acquisition and extinction of conditioned food reflex was studied in rats. It was found that vasopressin and its fragments had a more pronounced specific effect on the higher nervous activity of the animals. This effect consisted in impairment of the performance of the conditioned food reflex while oxytocin had a tendency to improve its performance. On the ground of the obtained data it is suggested that administration of vasopressin may facilitate the memory function only under specific environmental conditions.

[Analysis of the effect of cholecystokinin octapeptide on the monoamine level in rat brain limbic structures in the process of satiation]. / Analiz vliianiia oktapeptida kholetsistokinina na uroven' monoaminov limbicheskikh struktur mozge v protsesse nasyshcheniia.

The authors studied the changes in monoamine levels in rat brain limbic structures during natural satiation and satiation after intraperitoneal injection of cholecystokinin octapeptide (CCK-8) in doses 5 and 10 micrograms/kg following 24- and 48-hour food deprivation. Injection of CCK-8 was found to reduce food consumption in hungry rats by 2.5 times on an average. Of the test animals, 25% appeared resistant to CCK-8, showing no reduction in food consumption. Satiation after the 24-hour food deprivation caused characteristic changes in the levels of noradrenaline, dopamine and serotonin in the limbic structures of the brain, similar to the changes in monoamine levels in the limbic structures of animals, in which food motivation was suppressed by injection of CCK-8. The responses of the monoaminergic system of the brain limbic structures to satiation induced by CCK-8 injection after the 48-hour food deprivation differed qualitatively from the responses to natural satiation. It is concluded that the inhibitory action of CCK-8 on food motivation in rats determined by the 24-hour fasting is likely to be mediated via the monoamine system of the hypothalamus, tonsils and hippocamp. However, the data obtained suggest a different mechanism of the satiating action of CCK-8 under marked food motivation after long-term periods of food deprivation.

[Effect of cholecystokinin octapeptide on brain monoamine levels during feeding and drinking motivational excitation]. / Vliianie oktapeptida kholetsistokinina na uroven' monoaminov mozga v usloviiakh pishchevogo i pit'evogo motivatsionnykh vozbuzhdenii.

The paper presents studies of the influence of octapeptide cholecystokinin (ChCK-8) on the level of dofamine, noradrenaline and serotonine in the hypothalamus, septum, amygdala, striatum and mesencephalon of the rats brain during 24-, 48- and 96-hour alimentary and water deprivation. A change of catecholamines content under the influence of ChCK-8 was observed for the most part in conditions of thirst and only in the hypothalamus. ChCK-8 action in conditions of water deprivation was selective and directed mainly to the restoration of the changes in transmitter's level. ChCK-8 did not have a significant influence on the level of the brain monoamines during hunger. It may be assumed, that "satiation" hormone ChCK-8 is to a great extent connected with the mechanisms of reinforcement, and its "satiating" effect would appear at catecholamines' level in the process of satisfying of corresponding need.