1. |
- Fahlke, Claudia, 1964, et al.
(author)
-
Involvement of corticosterone in the modulation of ethanol consumption in the rat.
- 1994
-
In: Alcohol (Fayetteville, N.Y.). - 0741-8329. ; 11:3, s. 195-202
-
Journal article (peer-reviewed)abstract
- Several studies report that rats exposed to stressful conditions may increase their ethanol consumption. Stress is accompanied by a rise in the secretion of adrenocortical hormones, and the possibility that these hormones exert an influence on ethanol consumption should be considered. The present investigation addressed this issue by studying the effect of adrenalectomy (ADX) and subsequent corticosterone (CORT) or aldosterone (ALDO) treatment on ethanol intake. The results showed that ADX rats decreased their ethanol intake compared to the sham-operated controls and that treatment with CORT restored the intake of ethanol to the preoperative level. In contrast, treatment with ALDO (0.25 or 0.75 mg/kg) had no effect on ethanol intake. Biochemical analyses showed increases in monoamine turnover in the brain stem and limbic forebrain after ADX. The reduction of ethanol consumption caused by ADX may thus be specifically attributed to the loss of one of the adrenal hormones, CORT. The results indicate that CORT may be a factor of importance in the modulation of alcohol consumption.
|
|
2. |
- Allard, Per, et al.
(author)
-
Loss of dopamine uptake sites labeled with [3H]GBR-12935 in Alzheimer's disease.
- 1990
-
In: European Neurology. - 0014-3022 .- 1421-9913. ; 30:4, s. 181-5
-
Journal article (peer-reviewed)abstract
- The binding of the dopamine uptake inhibitor [3H]GBR-12935 to postmortem putamen from a control group and patients with Alzheimer's disease/senile dementia of Alzheimer type (AD/SDAT) or vascular dementia (VD) was studied. The binding density (Bmax) in AD/SDAT was significantly reduced to 50% of control. A reduction of Bmax in VD was also noted, but it did not reach statistical significance. No differences in apparent binding affinity (Kd) between controls and dementia groups were obtained. The concentrations of dopamine (DA), dihydroxyphenylacetic acid (DOPAC), 3-methoxytyramine (3-MT) and homovanillic acid were also determined. The concentrations of DA and DOPAC were reduced by 30-40% in AD/SDAT and VD, but the reductions did not reach statistical significance. The concentration of 3-MT was reduced by 40% in AD/SDAT and by 30% in VD. The [3H]GBR-12935-binding densities correlated significantly with corresponding concentrations of DA in control brains. It is suggested that the loss of [3H]GBR-12935-binding sites in human putamen in AD/SDAT reflects a degeneration of dopamine neurites.
|
|
3. |
- Erlandson, R. E., et al.
(author)
-
Freja observations of electromagnetic ion cyclotron ELF waves and transverse oxygen ion acceleration on auroral field lines
- 1994
-
In: Geophysical Research Letters. - 0094-8276. ; 21:17, s. 1855-1858
-
Journal article (peer-reviewed)abstract
- Extremely low-frequency (ELF) magnetic and electric field plasma wave emissions were recorded on 2 October 1993 on auroral field lines by the Magnetic Field Experiment during Freja orbit 4770. The ELF wave frequencies were below the local oxygen gyrofrequency (25 Hz) and between the helium and proton gyrofrequencies (100 to 400 Hz). The ELF waves, interpreted as electromagnetic ion cyclotron (EMIC) waves, were observed in a region of inverted-v-type electron precipitation. The EMIC waves were correlated over time with auroral and lower energy (≈ 100 eV) electrons, which are both possible sources of free energy, and also with transversely accelerated oxygen ions. The waves above the helium gyrofrequency were more closely correlated with the transverse oxygen ion acceleration than the waves below the oxygen gyrofrequency. These observations are consistent with a scenario in which electron beams generate EMIC waves, which then produce transverse oxygen ion acceleration through a gyroresonant interaction.
|
|
4. |
- Fahlke, Claudia, 1964, et al.
(author)
-
Audiogenic immobility reaction and open-field behavior in AA and ANA rat lines.
- 1993
-
In: Alcohol (Fayetteville, N.Y.). - 0741-8329. ; 10:4, s. 311-5
-
Journal article (peer-reviewed)abstract
- Individual predispositions in emotional reactivity have been suggested as factors involved in the development of alcoholism. To approach this problem, we assessed emotional reactivity in alcohol-naive animals from the alcohol-preferring (AA) and alcohol-avoiding (ANA) rat lines of Alko Ltd. AA rats are known to have higher brain levels of 5-hydroxytryptamine (5-HT) than ANA rats. Emotional reactivity was therefore assessed by an audiogenic immobility reaction (freezing), which is specifically sensitive to and shortened by depletion of 5-HT. The results showed that AA rats of both sexes displayed increased immobility reactions compared to the corresponding sex of the ANA rats. During the period of adaptation to the test cage ANA rats of both sexes showed increased locomotor activity compared to the corresponding sex of the AA rats. Levels of plasma corticosterone did not differ between the rat lines, either during resting or stressful conditions. The present results suggest that a passive, inhibited style of defensive behavior is associated with a high alcohol consumption.
|
|
5. |
- Tiensuu Janson, Eva, et al.
(author)
-
[111In-DTPA-D-Phe1]octreotide scintigraphy in patients with carcinoid tumours : the predictive value for somatostatin analogue treatment
- 1994
-
In: European Journal of Endocrinology. - : Oxford University Press (OUP). - 0804-4643 .- 1479-683X. ; 131:6, s. 577-581
-
Journal article (peer-reviewed)abstract
- This study was performed to evaluate whether the presence or absence of somatostatin receptors in malignant carcinoid tumours detected by [111In-DTPA-D-Phe1]octreotide scintigraphy can be used to predict response to somatostatin analogue treatment. Thirty patients were investigated, 28 with midgut carcinoid tumours and two with foregut carcinoid tumours. Twenty-seven patients showed pathological uptake in tumour lesions at scintigraphy; of these, 22 responded to somatostatin analogue treatment using octreotide, somatuline or octastatin, while five patients failed to respond. None of the three patients displaying negative scintigraphic investigations responded to treatment with somatostatin analogues. These results show a good correlation between the somatostatin receptor status and the patients' ability to respond to somatostatin analogue treatment (p = 0.014). We conclude that somatostatin receptor scintigraphy using [111In-DTPA-D-Phe1]octreotide can be used to select patients with malignant carcinoid tumours suitable for somatostatin analogue treatment and exclude those that will not benefit from such medication.
|
|