Expression of tilapia prepro-melanin-concentrating hormone mRNA in hypothalamic and neurohypophysial cells.

Melanin-concentrating hormone (MCH) is a neuropeptide involved in background adaptation in teleost fish, and in multiple regulatory functions in mammals and fish. To study the expression of the MCH preprohormone (ppMCH) in teleosts, we first cloned a hypothalamic cDNA encoding the complete ppMCH of tilapia (Oreochromis mossambicus), and a cRNA probe derived from a 270 bp ppMCH cDNA fragment was used for the expression studies. The level of ppMCH mRNA expression in tilapia hypothalamus, measured by dot blot analysis, was significantly higher in fish adapted to a white background than in black-adapted animals, which is in accordance with the reported MCH plasma and tissue concentrations in fish.

Effects of remacemide and its metabolite FPL 12495 on spike-wave discharges, electroencephalogram and behaviour in rats with absence epilepsy.

The effects of the anti-convulsant drug remacemide and one of its active metabolites FPL 12495 were examined in a genetic model for generalized absence epilepsy, the WAG/Rij strain of rats. Number, mean and total duration of spike-wave discharges were measured following oral administration of remacemide and FPL 12495, together with parameters of background electroencephalographic activity (EEG) and spontaneous behaviour in the recording cage. A decrease in the number of the spike-wave discharges was found after remacemide administration.

Kappa opioid receptor agonists suppress absence seizures in WAG/Rij rats.

Involvement of the kappa opioid receptor in the regulation of epileptic activity was studied in WAG/Rij rats, a genetic model of absence epilepsy. I.c.

Effects of diazepam on encoding processes.

Benzodiazepines are known to induce amnesic effects. To specify these effects more precisely, 40 healthy volunteers were given 15 mg diazepam or placebo. Effects on a chain of encoding operations were investigated: activation of memory representations, spreading of activation, semantic encoding and organizational processes.

Effects of diazepam and buspirone on reaction time of saccadic eye movements.

Effects of the anxiolytic drugs diazepam and buspirone were studied on the reaction time of saccadic eye movements. The study was performed with 8 healthy volunteers in a double-blind, placebo-controlled way. The purpose was to investigate the putative drug effects on the first step of an attention shifting task: the disengagement of attention.

Neuronal activities underlying the electroencephalogram and evoked potentials of sleeping and waking: implications for information processing.

The low amplitude, high frequency waves of the electroencephalogram (EEG) indicative of wakefulness, are produced by a summation of potentials of thalamocortical neurons, which fire in a "tonic mode" of depolarization. In this mode, the transfer of information from the peripheral sense organs to the sensory cortex is facilitated, due to a tonic lowering of the discharge threshold of thalamocortical neurons. The transfer decreases during drowsiness when thalamocortical units are more hyperpolarized and have higher thresholds.

Role of L-type calcium channel modulation in nonconvulsive epilepsy in rats.

Old male Wistar rats spontaneously showing hundreds of spike-wave discharges daily were used to investigate the role of calcium ions in nonconvulsive epilepsy. The effects of the L-type calcium channel blocker nimodipine and the L-type channel opener BAY K 8644 on number and duration of these spike-wave discharges were investigated. In rats aged 84-94 weeks standard EEG electrodes were chronically implanted; animals were allowed to recover for 10 days.

Proenkephalin and prodynorphin mRNA level in brain of rats with absence epilepsy.

An in situ hybridization method was used to estimate the proenkephalin (PENK) and prodynorphin (PDYN) mRNA levels in the brain of epileptic 6-month-old WAG/Rij rats in comparison with non-epileptic: 3-month-old WAG/Rij rats, 3-month-old ACI rats and 6-month-old ACI rats. The epileptic rats had a significantly higher level of PENK mRNA in the striatum as compared to non-epileptic controls. The PDYN mRNA level was significantly elevated only in the hippocampus of epileptic rats, whereas age- or strain-related changes in the striatal and cortical PDYN mRNA levels were found in both epileptic and non-epileptic rats.

Effects of lamotrigine on absence seizures in rats.

Lamotrigine, a novel antiepileptic drug thought to inhibit the excitatory neurotransmitter release and indicated for convulsive seizures, was tested for its efficacy in modulating non-convulsive seizures of the absence type of epilepsy. This was done in a rat model for absence epilepsy: the WAG/Rij strain of rats. In side-effect free doses, lamotrigine did not inhibit absence seizures in these animals.

Additive action of partial heterokaryon incompatibility (partial-het) genes in Aspergillus nidulans.

We have observed partial heterokaryon-incompatibility reactions in combinations of field isolates of A. nidulans. We have demonstrated that partial heterokaryon incompatibility is genetically controlled by genes (partial-het genes) operating in the same manner as the previously-described het genes.

Effects of the neuroleptanalgesic fentanyl-fluanisone (Hypnorm) on spike-wave discharges in epileptic rats.

Effects of fentanyl-fluanisone (Hypnorm), a combination often used as a neuroleptanalgesic and anaesthetic, were investigated on spike-wave discharges of epileptic WAG/Rij rats. Fentanyl-fluanisone has stimulating effects on the amount of spike-wave discharges, but not in a dose-dependent manner. A low dose of 0.

Effects of mu and delta opioid receptor agonists and antagonists on absence epilepsy in WAG/Rij rats.

The effects of various types of opioid receptor agonists and antagonists were determined in a genetic rat model for generalized absence epilepsy. Rats of the WAG/Rij strain spontaneously showed several hundred spike-wave discharges per day. Intracerebroventricular (i.

Island living: the experience of loneliness in a psychiatric hospital.

The purpose of this study was to examine perceptions of loneliness among psychiatric patients. The sample included 12 adults receiving treatment in a psychiatric facility. Data consisted of audiotaped semistructured interviews.

Hypoxic-ischemic encephalopathy sustained in early postnatal life may result in permanent epileptic activity and an altered cortical convulsive threshold in rat.

The aim of this study was to investigate whether the rat cerebral cortex, damaged by hypoxia-ischemia in early postnatal life, would show an increased seizure susceptibility and/or spontaneous epileptic discharges in adulthood. To that end 12-13-day-old Wistar rat pups were unilaterally exposed to hypoxic-ischemic conditions. After a recovery period of about 2.

Interactions between NMDA and nonNMDA receptors in nonconvulsive epilepsy in the WAG/Rij inbred strain.

The interaction between NMDA and nonNMDA receptors was studied in nonconvulsive epilepsy in WAG/Rij rats. Compounds acting on NMDA (NMDA, APH) and nonNMDA (AMPA, GDEE, kainic acid, kynurenic acid) receptors were coinjected intracerebroventricularly. The WAG/Rij rat strain may be an animal model for human nonconvulsive absence epilepsy.

The WAG/Rij rat model for nonconvulsive absence epilepsy: involvement of nonNMDA receptors.

The involvement of AMPA and kainate receptors in nonconvulsive epilepsy was studied by intracerebroventricular injections of AMPA, GDEE, kainic acid and kynurenic acid in WAG/Rij rats. The WAG/Rij rat strain is recognized as an animal model for human absence epilepsy. EEG registrations showed that AMPA (0.

Aberrant transients in the EEG of epileptic rats: a spectral analytical approach.

Aberrant transients in the cortical electroencephalogram of rats of the epileptic WAG/Rij strain were studied by means of spectral analysis. The EEG of rats of this strain contains, besides normal sleep spindles, high-voltage spiky phenomena, epileptic spike-wave discharges, and deviant intermediate stage. Spectral analysis of these transient phenomena shows that some features, like their peak frequency, are alike, but that they differ in other spectral characteristics, as in the first harmonic of the peak frequency and in the domain of the high frequencies.

Thalamic multiple-unit activity underlying spike-wave discharges in anesthetized rats.

In epilept WAG/Rij rats, multiple unit activity coinciding with the occurrence of spike-wave discharges was recorded under neurolept anesthesia. Recordings were made in the frontal cortex and in various nuclei of the thalamus, in specific nuclei such as the ventroposterolateral, the ventroposteromedial and the ventrolateral nuclei, as well as in non-specific nuclei such as the mediodorsal nucleus, the reticular thalamic nucleus, the interanteromedial nucleus and the intralaminar nuclei (the central medial nucleus, the centrolateral nucleus and the paracentral nucleus). Rhythmic unit firing concurrent with the spike component of the cortical spike-wave discharge was observed in deep layers of the cortex and in the following thalamic nuclei: in specific nuclei, the mediodorsal and the reticular thalamic nucleus.

Involvement of fibronectin during epiboly and gastrulation in embryos of the common carp, Cyprinus carpio.

The present report firstly describes a pilot study in which, during early development of embryos of the common carp, Cyprinus carpio, the cellular adhesion to fibronectin (FN) was blocked by administration of GRGDS peptide (which binds to the FN-receptor). As this treatment resulted in developmental aberrations, suggesting a functional role for FN, the major part of the work was focussed on the distribution of reactivity of anti-FN antibodies during epiboly and gastrulation. GRGDS treatment had a concentration dependent effect on development.

Influence of diazepam on prospective time estimation.

24 students, after intake of diazepam or placebo, performed a psychomotor test of finger tapping as a prospective time-estimation task. The task was less overestimated by those who were under the influence of the drug than by the 12 subjects to whom the placebo was given.

Effects of loreclezole on epileptic activity and on EEG and behaviour in rats with absence seizures.

The antiepileptic profile of loreclezole, a new putative antiepileptic compound, has been determined in rats of the WAG/Rij strain, a genetic model of generalized absence epilepsy. In addition, the effects of 0, 5, 10 and 20 mg/kg loreclezole on the spectral content of the background EEG and on spontaneous behaviour of rats were investigated. Both the number of spike-wave discharges and their total duration dose-dependently decreased following administration of loreclezole.

Degradation of some phenols and hydroxybenzoates by the imperfect ascomycetous yeasts Candida parapsilosis and Arxula adeninivorans: evidence for an operative gentisate pathway.

The imperfect ascomycetous yeasts Candida parapsilosis and Arxula adeninivorans degraded 3-hydroxybenzoic acid via gentisate which was the cleavage substrate. 4-Hydroxybenzoic acid was metabolized via protocatechuate. No cleavage enzyme for the latter was detected.

Some solvents for antiepileptics have proepileptic potencies in the WAG/Rij rat model for absence epilepsy.

Some solvents for antiepileptics were tested, for 4 consecutive days, in a rat model (the WAG/Rij inbred strain) for absence epilepsy. Electroencephalogram registrations and behavioral observations suggested that both Tween-80 and a mixture of saline/ethanol/propylene glycol caused an increase in the number of epileptic phenomena. This increase was not significant and restricted to injection day 1 with Tween-80 but was significantly present during all 4 injection days with the saline/ethanol/propylene glycol mixture.

Effects of the beta-carboline abecarnil on epileptic activity, EEG, sleep and behavior of rats.

The profile of the anxiolytic beta-carboline isopropyl 6-benzyloxy-4-methoxymethyl beta-carboline-3-carboxylate (abecarnil; ZK 112 119), a partial agonist at benzodiazepine receptors, was determined in two experiments. In the first, abecarnil was given to WAG/Rij rats; these rats generate spontaneously occurring spike-wave discharges and are regarded as a model for absence epilepsy. Effects were measured on epileptic activity, together with those on the spectral content of the background electroencephalograph (EEG), as well as on ongoing behavior.

Genetic models of absence epilepsy, with emphasis on the WAG/Rij strain of rats.

In this review, the main characteristics of genetic models of absence epilepsy, in particular with respect to WAG/Rij rats, are presented. Genetic models are important and relevant, since evidence exists that these models mimic spontaneously occurring human epilepsy more than models in which epilepsy is artificially induced. Genetic models can be divided into models in which seizures are elicited and into those in which epilepsy appears without any sensory stimulation.