[Effect of microapplications of cholecystokinin octapeptide on neurons of the dorsal hippocampus of alert rabbits].

The hormonally active fragment of the intestinal hormone cholecystokinin applied microiontophoretically or under pressure to the hippocampal neurons (fascia dentata and CA3 field) more or less depressed their spontaneous firing rate depending on the dosage. The neurons sensitivity to L--glutamate did not essentially change, at that. Neurons with burst--like firing started to reveal a regular patterns of firing.

Effects of cholecystokinin octapeptide and its fragments on brain monoamines and plasma corticosterone.

The effects of intracerebroventricular administration of an 80 pmole dose of cholecystokinin octapeptide sulphate ester, unsulphated cholecystokinin octapeptide and their fragments were tested on the dopamine, norepinephrine and serotonin contents of the rat hypothalamus, mesencephalon, amygdala, septum, cerebral cortex and striatum, as well as on the plasma corticosterone level. Cholecystokinin octapeptide sulphate ester and the tyrosine-sulphate-methionine and tyrosine-sulphate-methionine-glycine fragments increased the dopamine and norepinephrine contents of the hypothalamus and mesencephalon. The same compounds increased the dopamine content of the amygdala, while they decreased the dopamine and norepinephrine concentrations in the striatum.

Effect of cholecystokinin antiserum on the brain monoamine content in rats.

The effects of intracerebroventricular administration of cholecystokinin (CCK) antiserum )specific for COOH-terminal four amino acids) of CCK were tested in three dilutions on the dopamine (DA), norepinephrine (NE) and serotonin (5-HT) contents of the hypothalamus, amygdala, septum, striatum and cerebral cortex in rats 24 h following application. CCK antiserum decreased the DA and NE contents in the hypothalamus, mesencephalon, amygdala and septum, while it increased the DA content and decreased the NE content of the striatum. It had a slight effect on the 5-HT contents of the amygdala, septum and striatum.

Modulation of passive avoidance behaviour of rats by intracerebroventricular administration of cholecystokinin octapeptide sulfate ester and nonsulfated cholecystokinin octapeptide.

The effects of intracerebroventricular administration of different doses of cholecystokinin octapeptide sulfate ester (CCK-8-SE) and nonsulfated cholecystokinin octapeptide (CCK-8-NS) were tested on the latency of passive avoidance behaviour in rats. Treatments were carried out prior to learning trial, immediately after electroshock and prior to testing 24 h retention. Both CCK-8-NS and CCK-8-SE enhanced the latency of passive avoidance after all forms of treatment while showing different dose-response patterns depending on time of administration.

Effects of intraventricular administration of cholecystokinin octapeptide sulfate ester and unsulfated cholecystokinin octapeptide on active avoidance and conditioned feeding behaviour of rats.

The effects of cholecystokinin octapeptide sulfate ester (CCK-8-SE) and unsulfated cholecystokinin (CCK-8-NS) were studied following intraventricular administration on active avoidance and conditioned feeding behaviour of rats. In the CCK-8-NS and CCK-8-SE treated animals the acquisition of active avoidance and conditioned feeding behaviour were considerably impaired compared to the control; furthermore, these peptides caused a facilitated extinction of active avoidance and conditioned feeding behaviour. The data suggest that cholecystokinin octapeptide is capable of modifying the fear and hunger motivated behaviours of rats.

Effect of cholecystokinin octapeptide sulphate ester on brain monoamines in the rat.

The effect of different doses of intracerebro-ventricularly administered cholecystokinin octapeptide sulphate ester (CCK-8-SE) was studied on dopamine (DA), norepinephrine (NE) and serotonin (5-HT) contents in the hypothalamus, mesencephalon, amygdala, septum and striatum, 10, 20 and 60 min following administration. The DA and NE content increased and the 5-HT content decreased in the hypothalamus and mesencephalon. A biphasic action was observed in the amygdala of DA, NE and 5-HT depending upon the time and doses used.

Influence of cholecystokinin octapeptide sulfate ester on brain monoamine metabolism in rats.

The effects of intracerebroventricular administration of an 80 pmole dose of cholecystokinin octapeptide sulfate ester (CCK-8-SE) were tested on the dopamine (DA), norepinephrine (NE) and serotonin (5-HT) turnovers of the hypothalamus, mesencephalon, amygdala, septum, striatum and cerebral cortex in rats. CCK-8-SE in an 80 pmole dose decreased the DA turnovers of the hypothalamus, mesencephalon, amygdala and septum, while it increased that of the striatum. The NE turnovers were increased in the hypothalamus and amygdala, but decreased in the striatum.

Lack of correlation between hypothalamic serotonin and the ether-induced ACTH secretion in adrenalectomized rats.

The central serotonergic system was manipulated using a serotonin receptor antagonist (cyproheptadine), electrolytic lesioning of the raphe nuclei and neurochemical destruction of the serotonergic terminals in the hypothalamus. The effects of these interventions on ether-induced ACTH secretion were studied in adrenalectomized rats. Serotonin, norepinephrine and dopamine concentrations were measured in the medial basal hypothalamus (MBH) or in individual nuclei of the hypothalamus and of certain midbrain regions.

Pharmacology of GYKI-41 099 (chlorpropanol, Tobanum) a new potent beta-adrenergic antagonist.

The compound GYKI-41 099, as a beta-adrenergic antagonist, is 3-8 times more potent than propranolol in vitro and in vivo. Its antiarrhythmic effectiveness surpasses that of propranolol and pindolol inhibiting the ouabain arrhythmia in dogs and cats. GYKI-41 900 has a negligible cardiodepressant activity; it is not cardioselective.

Adrenergic innervation of the rat hypothalamus.

The adrenergic innervation of the hypothalamus was studied by measuring hypothalamic adrenaline levels following surgical transection of the lower brain stem or electrolytic lesion of the medullary adrenaline-containing cell groups. The adrenaline levels in some hypothalamic nuclei and in the median eminence showed a slight decrease after partial transection of the medulla oblongata, whilst there was a pronounced decrease (by 59-78%) 7-10 days following total hemisection or unilateral lesion of the C1-catecholaminergic cell group in the medulla oblongata.

Effects of reserpine and antidepressants on dopamine and DOPAC (3,4-dihydroxyphenylacetic acid) concentrations in the striatum, olfactory tubercle and median eminence of rats.

The dopamine, noradrenaline and 3,4-dihydroxyphenylacetic acid (DOPAC) levels of various rat brain areas (median emience, olfactory tubercle, rostral and caudal part of the striatum) were measured. The effects of reserpine and antidepressants: amitriptyline, nomifensine and EGYT 475 (1-benzyl-4-/2'-piridylcarbonyl/piperazine) were investigated. The dopamine content of the median eminence proved to be the most sensitive to the depletory effect of reserpine.

Noradrenergic innervation of the rat hypothalamus:experimental biochemical and electron microscopic studies.

The concentrations of noradrenaline in individual hypothalamic nuclei and in the median eminence were measured 7-10 days following surgical transections of the lower brain stem or electrolytic lesions of the medullary noradrenaline-containing cell groups. Terminal degeneration in the hypothalamus was studied after the same surgical procedures. Direct, monosynaptic connections between the dorsomedial hypothalamic nucleus and all the noradrenaline-containing cell groups investigated were found.

Studies on the prolactin response induced by electroconvulsive therapy in schizophrenics.

Electroconvulsive therapy (ECT) and simulated ECT (SECT)-induced prolactin response has been studied in 14 schizophrenic males. Cortisol, growth hormone, and thyroid stimulating hormone (TSH) changes have been measured simultaneously. The prolactin rise was significantly higher after ECT than after SECT.

[Effect of etimizol on behavioral responses, brain serotonin concentration and plasma corticosteroid levels].

The influence of ethymisol on behavioural reactions was studied on 100 albino rats in the "open field" and "passive avoidance" tests. It was shown that a 5 mg/kg dose of this neurotropic drug with synaptic effect, changes behavioural reactions, lowers the general emotional stress and emotional memory of the electro-cutaneous stimulation. Simultaneously the level of corticosteroids in the blood plasma significantly rises, while the serotonin content in the hypothalamus decreases.

Distribution of norepinephrine and dopamine in cerebral cortical areas of the rat.

Concentrations of norepinephrine and dopamine were determined using enzyme isotope assay in 27 microdissected cerebral cortical areas of the rat. A detailed map is presented for microdissection of rat cerebral cortex. Norepinephrine was found in low but still measurable quantities throughout the cortex.

Neonatal indirect hyperbilirubinaemia in twins.

Neonatal indirect hyperbilirubinaemia in 21 pairs of twins was compared and studied during the first postnatal week. Peak bilirubin concentration and the persistence of icterus was similar in the two sets of twins, but considerable individual inter-twin differences could be obeserved. Various postnatal parameters and inter-twin differences in these parameters were correlated with differences in hyperbilirubinaemia.

Plasma corticosterone level of rats after bilateral lesion of the globus pallidus and elimination of the sex-dependence of the body weight loss following pallidal lesion by bilateral adrenalectomy.

Plasma corticosterone (CST) level and body weight were studied in male and female rats after bilateral pallidal lesion (GPL). The effect of high dose of glycocorticoids on body weight of food and water deprived, non-lesioned rats was also studied since high CST levels due to the stress caused by the aphagia and adipsia could be anticipated. Weight changes in lesioned-adrenalectomized animals were in investigated as well.

Dopamine, noradrenaline and 3,4-dihydroxyphenylacetic acid (DOPAC) levels of individual brain nuclei, effects of haloperidol and pargyline.

Noradrenaline (NA), dopamine (DA) and DOPAC were determined with a newly developed radioenzymatic method simultaneously in the striatum, limbic system, hypothalamus and in catecholamine-containing cell groups of the rat brain. Only a loose relationship could be established between DOPAC and DA contents in the various brain areas. The lowest relative DOPAC level (DOPAC/DA ratio) was found in the median emience, while it was the highest in the periventricular nucleus of the hypothalamus.