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Neuropeptide cholecystokinin (CCK) has been reported to suppress ethanol intake, but there is contradictory evidence about the role of CCK(2) receptors. In the present study anxiolytic, hypolocomotor and sedative effects of acute ethanol administration, but also voluntary ethanol consumption were studied in male and female mice, lacking CCK(2) receptors (-/-). Ethanol (1.0 and 2.0 g/kg) induced a significant reduction of anxiety-related behaviours in the elevated plus-maze, but this effect was statistically significant only in female homozygous mice (-/-). In male mice, lacking CCK(2) receptors (-/-), but not in their wild-type littermates (+/+), the suppression of vertical locomotor activity was caused by ethanol at a dose 0.5 g/kg. The highest dose of ethanol (2.0 g/kg) produced statistically significant reduction of horizontal locomotor activity only in female wild-type (+/+) mice, but this effect was related to increased basal activity when compared to female mutant (-/-) mice. Duration of the loss of righting reflex was not significantly affected by genotype or gender, but blood ethanol levels at regain of righting reflex were significantly lower in female homozygous mice (-/-) compared to their wild-type (+/+) littermates, indicating increased sensitivity to the sedative effect of ethanol. Ethanol intake, but not preference, at concentration 10% was significantly increased in female mice, lacking CCK(2) receptors (-/-). The present study revealed an altered response to the acute effects of ethanol in CCK(2) receptor deficient mice (-/-). These changes are gender-specific and could be attributed to the altered activity of dopaminergic system in male mice and increased activity of GABA-ergic system in female mice as established in our previous studies.

Src family kinases (SFKs) are non-receptor-type protein tyrosine kinases that were originally identified as the products of proto-oncogenes and were subsequently implicated in the regulation of cell proliferation and differentiation in the developing mammalian brain. Recent studies using transgenic mouse models have demonstrated that SFKs that are highly expressed in the adult brain regulate neuronal plasticity and behavior through tyrosine phosphorylation of key substrates such as neurotransmitter receptors. Here, we provide an overview of these recent studies, as well as discussing how modulation of the endocytosis of neurotransmitter receptors by SFKs contributes, in part, to this regulation. Deregulation of SFK-dependent tyrosine phosphorylation of such substrates might underlie certain brain disorders.

AbstractLocalized two‐dimensional constant‐time correlation spectroscopy (CT‐COSY) was used to resolve glutamate (Glu), γ‐aminobutyric acid (GABA), and glutamine (Gln) in the human brain at 4.7 T. In this method, three‐dimensional localization was achieved using three radio frequency pulses of the CT‐COSY module for slice selection. As this sequence could decouple JHH along the F1 direction, peak resolution of metabolites was improved even on a magnitude‐mode display. In experiments on a phantom containing N‐acetylaspartate, creatine, Glu, Gln, and GABA with a constant time delay (Tct) of 110 ms, cross peaks of Glu, Gln, and GABA were obtained on a spectrum processed with standard sine‐bell windows, which emphasize sine‐dependent signals along the t2 direction. In contrast, diagonal peaks of Glu C4H at 2.35 ppm, GABA C2H at 2.28 ppm, and Gln C4H at 2.44 ppm were resolved on a spectrum processed with Gaussian windows, which emphasize cosine‐dependent signals along t2. Human brain spectra were obtained from a 27 mL voxel within the parieto‐occipital region using a volume transverse electromagnetic (TEM) coil for both transmission and reception. Tct was 110 ms; the total scan time was 30 min. Diagonal peaks of Glu C4H, GABA C2H, and Gln C4H were also resolved on the spectrum processed with Gaussian windows. These results show that the localized two‐dimensional CT‐COSY method featuring 1H decoupling along the F1 direction could resolve Glu, GABA, and Gln signals in the human brain. Copyright © 2008 John Wiley & Sons, Ltd.

We examined tryptophan and serotonin (5-hydroxytryptamine) levels in the blood after consumption of alcohol. Forty-five minutes after drinking, whole blood serotonin concentration was significantly reduced, whereas no changes were observed in tryptophan level. The diurnal rhythm of 5-HT in subjects who the day before had drunk alcohol was quite different from the control group, but very similar to that of patients with depression. The results strongly suggest that the mechanism of depression after alcohol drinking may be related to serotonin.

Research on the interaction of ethanol and stress with experimental animals are briefly reviewed. There might be the two aspects of the interaction of stress and ethanol, i.e., how stress affects ethanol ingestion and response to ethanol, and how ethanol modifies stress response. In general, stress increases ingestion of ethanol in animals exposed to various stresses including electric shock, immobilization and psychological or emotional stresses, wherein the psychological or emotional factors were predominantly involved. However, in most cases, ethanol ingestion is increased after release from stress not during exposure to stress. A variety of stressful stimuli caused marked increases in the neurotransmitter release in many brain regions. Immobilization stress increased noradrenaline release in the extended brain regions in rats. These increases were significantly attenuated by pretreatment with ethanol in the rat amygdala and locus coeruleus, but not in the hypothalamus, although ethanol by itself increased noradrenaline release in the hypothalamus. Further, psychological stress, wherein the rats were given no electrical shock, but exposed to the emotional responses such as struggling, vocalization, jumping and defecation shown by the other electrically-shocked rats, increased noradrenaline release preferentially in the hypothalamus, amygdala and locus coeruleus. Among the former two regions, stress-induced increases in noradrenaline release were significantly attenuated by ethanol in the amygdala, but not in the hypothalamus. Together with the finding that increases, in noradrenaline release are closely related to the provocation of anxiety and/or fear, ethanol, in part, reduced tension, as mentioned in the tension reduction hypothesis, by attenuating stress-induced increases in noradrenaline release in the amygdala and locus coeruleus. Moreover, ethanol, administered i.p. and directly through the microdialysis probe, increased dopamine release in the nucleus accumbens assessed by in vivo microdialysis, similarly as addictive drugs such as amphetamine did. This might be, in part, neurochemical basis for motivation of repeated drinking of ethanol.

The effect of ethanol on nitric oxide synthase (NOS) activity was examined histochemically and biochemically in cultured cerebral cells of chick embryos. The cells were isolated from 13- to 14-day-old chick embryos to which 10% ethanol (ethanol group) or saline (control) had been injected on the 3rd day of embryogenesis. Expression of NADPH diaphorase in cultured cells was stained using nitro blue tetrazolium (NBT). The activity of NOS was observed by the following 2 assays: NADPH diaphorase activity was determined using the substrate NBT with the cofactor NADPH, and NOS activity was determined by measurement as radiochemical activity of the conversion of [3H]L-arginine to [3H]L-citrulline. The number of isolated cells and viability from one cerebrum of chick embryo were 3 approximately 4 x 10(6) and more than 97%, respectively. In the neuronal cells, moderately positive expression of NADPH diaphorase was first detected on about the 3rd day of culture in both the control and ethanol group. The NADPH diaphorase and NOS activities in the isolated cells were higher in the ethanol group than in the control group. The NADPH diaphorase and NOS activities were significantly higher in the ethanol group than in the control group on the 4th and 2nd day of culture, respectively. These findings suggest that NO-released by elevated NADPH diaphorase activity and NOS activity is responsible for the induction of neuronal cell disorders attributed to chronic ethanol damage.

We studied the effect of prenatal exposure to alcohol on later circadian rhythm in the rat. In the normal light-dark cycle, an 8-h phase advance brought forward the deep body temperature rhythm in control rats, although it had a smaller effect in prenatally ethanol-exposed rats. In long constant darkness, the phase response of the deep body temperature rhythm to a light pulse at the early subjective night was less marked in ethanol-exposed rats in comparison to controls. These results indicate that prenatal exposure to alcohol has a long-lasting effect on the light responsiveness of the deep body temperature circadian rhythm.

We have previously shown that ethanol administration results in tyrosine phosphorylation of the 130 kDa protein in rat brain, and identified the protein as Cas, the crk-associated src substrate. In the present study, we demonstrate that Cbl of a 120 kDa protein is also tyrosine-phosphorylated in the cerebellum in response to ethanol administration. We also investigated whether Fyn kinase was involved in ethanol-induced Cbl phosphorylation. Immunoprecipitation experiments showed that the amount of coimmunoprecipitated Fyn kinase with an anti-Cbl antibody increased in extracts from ethanol-administered rats compared to those from saline-administered rats. Exogenous Fyn kinase was shown to phosphorylate on tyrosine residue(s) of Cbl from the cerebellum in vitro. Furthermore, Fyn kinase and Cbl were demonstrated immunohistochemically to be coexpressed in white matter in the cerebellum. These findings indicate that Cbl is tyrosine-phosphorylated in rat cerebellum in response to ethanol administration, and also raise the possibility that Fyn kinase may be involved in the process.

We report a 42-year-old female with alcohol addiction who suddenly died of subdural hematoma (SDH) caused by dural arteriovenous malformation (AVM). In autopsy, there was seen a massive SDH with a total weight of 181 g that covered an entire part of the left cerebral hemisphere, although either serious external injuries of the head or any visible internal injuries of the brain were observed. SDH subsequently resulted in the tonsillar, transtentorial and subfalcial herniations with a right-sided shift of the left-lateral and third ventricles, and the left thalamus as well. Histopathological examination on the serial sections cut from the falx cerebri revealed abnormal distribution of arteries and veins with various sizes, which were comprehensively highlighted by immunohistochemical stainings with alpha-SMA and CD31. Although a very point of bleeding was not identified even by careful histological observation, we concluded that dural AVM could be critical for acute SDH in the present case. The value of ethanol concentration examined in the samples from SDH supported that the lesion could be not chronic, but acute.