The effects of some neuropeptides infused into the cerebral ventricles on the spontaneous cerebral electric activity were studied in unanasthetized rabbits. The following peptides were investigated: physalaemin, caerulein, bombesin, litorin (supplied by Farmitalia). The rabbits were prepared according to Monnier and Gangloff's [10] method in order to record the spontaneous cortical activity. Each of these substances affects the electroencephalographic (EEG) records in a specific and dose-related way. Bombesin induces a biphasic pattern (synchronization followed by a partial activation), litorin is partially activating and physalaemin brings about a marked desynchronization. In spite of the marked structural analogy between bombesin and litorin, their EEG effects differ.

Animals↗

PubMedDate not supplied

Centrally administered N-terminal fragments of ACTH (1-10, 4-10, 4-9) display convulsant properties in rabbits.

Electroencephalographic and behavioral effects of the following ACTH fragments: 1-4, 4-9, 4-11, 1-10, 4-10, 1-13, 1-17 and 1-24 were studied in rabbits. Sequences 4-9, 1-10 and 4-10 displayed some epileptic properties, i.e., they induced epileptic seizures (only electrographic or also behavioral) or increased hippocampal spiking. The 4-9 sequence seemed to be the common sequence responsible for these proconvulsant effects. The possible involvement of the enkephalinergic system is discussed.

Adrenocorticotropic Hormone↗

PubMedDate not supplied

EEG and behavioural effects of polyamines (spermine and spermidine) on rabbits.

The EEG and behavioural changes induced by the administration of polyamines (spermine and spermidine) were studied in rabbit. Spermine and spermidine were administered at different doses (200 and 400 micrograms) into the mesencephalic ventricle (i.c.v.) both as a bolus and in constant perfusion (60 min duration). We also studied the effects of methamphetamine (MA) in a group of rabbits pretreated with spermine and spermidine 200 and 400 micrograms i.c.v. as bolus. Spermine caused a dose-related cortical synchronization associated with a partial sedation; spermidine induced cortical synchronization at a low dose without any behavioural changes while at higher dose (after perfusion) cortical desychronization with an arousal behavioural pattern occurred. The possible interaction of these substances with the mesolimbic dopaminergic system is discussed on the basis of their potential neuroleptic action.

Animals↗

PubMedDate not supplied

Comparative study of the EEG profile of neuroleptics selective for D-1 or D-2 dopamine receptors in the rabbit.

The neuroleptics SCH 23390 and raclopride, which interact selectively with either D-1 or D-2 dopamine receptor, were studied for their effects on electroencephalographic (EEG) activity in the rabbit. Haloperidol (0.3 and 1 mg/kg intravenously, i.v.), which was used for comparison, induced synchronization of the cortical EEG activity. Spectral EEG analysis showed increase of power in the whole frequency range (0.1-38.5 Hz) and in all frequency bands in the cortex, whereas a slight decrease of slow and fast theta activity (3.7-7.2 and 7.2-12.2 Hz) was observed in the hippocampus. Animals appeared sedated and arousal response to somatosensory stimuli was markedly inhibited. SCH 23390 (0.03 and 0.3 mg/kg i.v.) induced periods of cortical synchronization and changes of spectral power qualitatively similar to those accompanying haloperidol administration. The drug slightly reduced the duration of arousal elicited by stimuli. Raclopride (1 and 3 mg/kg i.v.) induced weak EEG changes and little effect on arousal response to stimulation. There was an increase of slow wave activity which was particularly evident in the hippocampus. The data indicate that, although to a lesser degree, the D-1 receptor antagonist SCH 23390 induced EEG effects similar to those of haloperidol, whereas blockade of D-2 receptors by raclopride resulted in different patterns of EEG activity.

Animals↗

PubMedDate not supplied

Cerebrovascular disease and k-opioid receptors in the rabbit.

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Animals↗

PubMedDate not supplied

[Pourfour du Petit syndrome and intracranial aneurysms (author's transl)].

A 52 year old female suffered for more than 20 years from a recurrent pulsating headache on the left side. Clinical examination showed the retraction of the superior eyelid and mydriasis on the left. Exophthalmometry revealed 17 mm of protrusion for each eyeball. Angiographic investigations showed two little aneurysms: one of the anterior comunicating artery, the second of the left middle cerebral artery. In view of the clinical and angiographic findings the authors discuss the pathogenetic mechanisms of such oculo-sympthetic syndrome.

Electrocardiography↗

PubMedDate not supplied

[A case of presacral myelolipoma].

Myelolipoma is a rare benign pathology whose pathogenesis is still unclear. It is most frequently localised in the adrenal gland, followed by the presacral region, mediastinum, and perirenal and hepatic region. It varies in size from a few millimetres to several centimetres. The lesion is usually capsulated, detachable from the surrounding tissues and hypovascularised. In histological terms, it is composed of lipomatous and hematopoietic tissues. A 65-year-old female patient was referred to our unit after the finding of a nonbiopsied, pelvic mass during earlier surgery. The patient was in considerable pain owing to the extrinsic compression of the mass on abdominal and pelvic organs. Preoperative tests confirmed the presence of a voluminous presacral neoformation that appeared to have a possible medullary origin (chordoma or schwannoma). During surgery, the lesion was found to be capsulated and mainly adherent to the rectum. Histological analysis confirmed the myelolipomatous nature of the lesion. A review of 21 cases reported in the literature is presented.

Aged↗

PubMedDate not supplied

[The neuroendocrine aspects of chronic alcoholism: the effect of alcohol intake and its withdrawal].

Neuroendocrine dysfunctions, in part similar to those found in depression, are present in chronic alcoholism. The aim of this investigation was to evaluate the effects of chronic alcohol intake on cortisol secretion in basal conditions, after dexamethasone (DXT) suppression or corticotropin (ACTH) stimulation in 10 alcoholic men, during active drinking and after two weeks of alcohol withdrawal. The 24-hour, day- and night-time urinary cortisol and melatonin levels, and the effects of thyrotropin releasing hormone (TRH) on thyrotropin (TSH) and prolactin (PRL) secretions were studied in the same subjects. The data were correlated to the scores obtained by the Hamilton Rating Scale for depression and compared to those found in healthy subjects. Increased cortisol levels and the lack of DXT suppression of cortisol secretion are considered to be alcohol-dependent inasmuch as they disappear in most patients after alcohol withdrawal. The cortisol response to ACTH 1-24 infusion measured before and after alcohol withdrawal was similar in the patients we studied; moreover no significant difference was found between patients and controls. The increment of urine free cortisol levels in active alcoholics was not statistically significant. Urine cortisol levels became similar to those of the control subjects after alcohol withdrawal. The increased diurnal values of urine melatonin and the inversion of the physiological ratio between nocturnal and diurnal levels observed during alcohol intake became normal upon alcohol withdrawal. The TSH and PRL responses after the administration of 50 or 200 micrograms TRH were higher in alcoholics than in controls, while a blunted response is known to occur in depression.

Adult↗