Search PubMed⌕ Search

Biomedical subjects

L Wetterberg

Publications and source records attributed to L Wetterberg.

At least 19 recordsLinked to original sources
PubMed1992

Exclusion of linkage between the serotonin2 receptor and schizophrenia in a large Swedish kindred.

Family, twin, and adoption studies suggest that genetic factors play an important role in the etiology of schizophrenia. Detection of single gene(s) involved in a higher susceptibility to a hereditary disease is possible with linkage analysis. The effects of serotonin2-receptor antagonists on symptoms of schizophrenia suggest that a mutation in the gene coding for this receptor subtype might be involved in the pathophysiology of this disease. Recently a copy DNA encoding the serotonin 5-HT2 receptor has been isolated and with a human 5-HT2 receptor copy DNA probe the HTR2 locus has been mapped to chromosome 13. Using multipoint linkage analysis between schizophrenia and genetic markers spanning the region of the HTR2 locus, we were able to exclude linkage between this candidate gene and schizophrenia in a Swedish kindred. Given this result, we conclude that the serotonin 5-HT2 receptor gene itself is not a major susceptibility gene for schizophrenia in this family.

Chromosomes, Human, Pair 13↗
PubMed1992

Effect of short-term fasting on nocturnal melatonin secretion in obesity.

To investigate whether the function of pinealocytes is altered in obesity, nocturnal melatonin (MT) secretion was determined in nine healthy subjects and compared with that of eight obese individuals. Serum MT levels were measured every second hour between 6:00 PM and 8:00 AM, and total nocturnal MT secretion (as reflected by the MT incremental area), MT peak time, and nocturnal urinary MT excretion were determined. None of these parameters differed significantly in the two groups. The obese subjects were reinvestigated after 2 days of complete fasting. This caused a decrease in body weight and basal blood glucose levels of 2.6 +/- 0.2 kg (mean +/- SEM, P less than .001) and 1.5 +/- 0.2 mmol/L (P less than .001), respectively, whereas serum cortisol levels remained unchanged. Short-term fasting reduced nocturnal MT secretion, as evidenced by MT incremental areas, which were reduced from 2.01 +/- 0.26 before fasting to 1.64 +/- 0.26 nmol/L.h after fasting (P less than .02). MT secretion peaks were reached simultaneously, and urinary MT excretion values did not change significantly in fasting. To see whether glucose supplementation during short-term fasting would normalize nocturnal MT secretion, we gave an additional seven obese subjects eight small oral doses of glucose (each dose, 0.5 g/kg body weight) at regular intervals during a 2-day fast. Their body weight decreased by 2.8 +/- 0.4 kg (P less than .001), but blood glucose and cortisol concentrations were similar before and after the glucose-supplemented fast, as was the nocturnal MT secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1992

Blood levels of melatonin, serotonin, cortisol, and prolactin in relation to the circadian rhythm of platelet serotonin uptake.

Blood levels of melatonin, serotonin, cortisol, prolactin, and serotonin uptake by platelets were measured at 08:00, 14:00, 20:00, 02:00, and 08:00 hours in 10 healthy men who ranged in age from 27 to 35 years. The Km values of serotonin active transport by platelets were significantly correlated with melatonin blood levels. There were no other significant correlations. The secretion of steroid hormones and prolactin showed an increase at 02:00 hours; levels of prolactin decreased at 08:00 hours, but steroid levels continued to rise. This finding suggests either a direct effect of melatonin on serotonin active transport or the influence of the suprachiasmatic nucleus on serotonin uptake by platelets. It is also possible that there is a simultaneous decrease in serotonin uptake and decline from peak levels of melatonin due to the rise in steroid secretion.

Adult↗
PubMed1992

Visual rating of magnetic resonance images of human cerebrospinal fluid spaces and white brain matter: relation to sex and age in healthy volunteers.

The size of the cerebrospinal fluid spaces and the occurrence of white matter lesions were estimated from the intracranial volumes of 76 apparently healthy adult volunteers of different ages using 0.02-T/0.8-MHz magnetic resonance imaging. A relation between the occurrence of white matter lesions and the size of cerebrospinal fluid spaces independent of age could not be demonstrated. In men, white matter changes were more numerous and lateral ventricular size was larger, but sex differences were not statistically significant except for lateral ventricular size. The results confirm that age is the most significant parameter correlated with alterations in brain anatomy over time. Body mass and other clinical parameters were not influential factors in the present material.

Age Factors↗
PubMed1992

Quantitative estimations of cerebrospinal fluid spaces and brain regions in healthy controls using computer-assisted tissue classification of magnetic resonance images: relation to age and sex.

Computer-assisted tissue classification based on MR intensity values in spin echo and inversion recovery images were used for area measurements of different brain structures in 76 apparently healthy volunteers of various ages. The classification was made from transaxial sections through the basal ganglia and discriminated between brain tissue and cerebrospinal fluid. The measurements based on this discrimination demonstrated larger intracranial areas in men than women. In the total group, sex differences were not observed when the measured structures were corrected for interindividual differences in cranial size. In subjects older than 60 years relative lateral ventricular area was larger and relative brain area smaller in men than women. The lateral ventricles, the Sylvian fissures and the brain area showed the most marked relation to age. The age-relation was more marked for left hemispheric structures.

Adult↗
PubMed1992

MRI in psychiatry: 731 cases.

The frequency of brain pathology found in the 731 patients who underwent MRI scans in the present study was higher than expected on the basis of reports in the literature (Owens et al., 1980). This underlines the value of a simple MRI examination as an effective diagnostic complement in the investigation of patients with psychiatric symptoms that may have an underlying organic basis.

Adult↗
PubMed1992

Light therapy of depression; basal and clinical aspects.

The effects of treatment with bright light in different forms of depressive conditions are described. The therapeutic mode rests on the hypothesis that they will normalize disturbed diurnal rhythms. The results have been more favourable when light has been given in the morning compared with in the evening, and in patients with seasonal depression rather than in those with non-seasonal illness.

Animals↗
PubMed1992

Chromosomal aberrations in a patient with severe psychopathology.

The case of a female patient showing aggressive, compulsive, destructive behaviour, ritualistic faecal smearing, and hyperactivity is presented. The behaviour is long standing, therapy-resistant, and its aetiology is unknown, although it is seemingly associated with chromosomal abnormalities secondary to abnormal plasma factors.

Abnormalities, Multiple↗
PubMed1992

Age, alcoholism and depression are associated with low levels of urinary melatonin.

Two normal control populations, separated by 8,000 miles and 24 degrees of latitude, had similar six-month mean values for overnight urinary melatonin concentrations. These values were significantly higher than six-month values for depressed subjects and abstinent alcoholic subjects, while the means for the two clinical populations were similar. Age and urinary melatonin concentration in the control and clinical populations were inversely related, but the slopes of the linear regression equations were ten times steeper for the control populations than for the clinical populations. Differences in age and sex distributions accounted for some of the differences in values between controls and the clinical populations, although controls still differed from the clinical populations, even after sex and age were factored out. The disparate slopes for age and melatonin concentrations may contribute to some of the conflicting findings of studies comparing populations of different ages. The total melatonin content in the samples from alcoholic subjects, but not the depressed subjects, was lower than that for controls. The difference in the urinary melatonin concentration between the controls and the two patient groups was not accounted for by difference in duration of urine collection period, hours of sleep or body weight.

Adult↗
PubMed1991

T1 and T2 relaxation time estimates and brain measures during withdrawal in alcoholic men.

Twenty-four chronic alcoholic men were investigated with 0.02 Tesla/0.8 MHz magnetic resonance imaging on days 7-9 of acute alcohol withdrawal state. Estimates of T1 and T2 relaxation times were obtained from the white matter and basal ganglia nuclei in an axial section. This section was also used for area measurements of intracranial structures using computer-assisted tissue classification. The relation between T1 and age was more marked in the alcoholic patients than in the control group. Mean values of T1 and T2 did not differ between the two groups, but differences in the age dependence of T1 were highly significant for all regions. The number of years of drinking was influential to T1, but to a lesser extent than age. Lateral ventricular area correlated significantly with T1 of the white matter in the alcoholic patients. Using visual ratings of the entire intracranial volume the alcoholic patients demonstrated wider lateral ventricles and cortical sulci, but there was no increased frequency of white matter lesions.

Adult↗
PubMed1991

No linkage between D2 dopamine receptor gene region and schizophrenia.

The dopamine hypothesis is one of the major etiological hypotheses of schizophrenia. The well-established role of genetic factors in schizophrenia together with reports of increased D2 dopamine receptor densities in untreated schizophrenic patients support the D2 dopamine receptor gene as a strong candidate gene for schizophrenia. The recent cloning of the D2 dopamine receptor gene made it possible to test the involvement of the D2 dopamine receptor locus (DRD2) in a large Swedish and a smaller Californian schizophrenia pedigree. Using multipoint linkage analysis between schizophrenia and a genetic map that includes the DRD2 locus and assuming a dominant mode of inheritance, we were able to exclude the DRD2 locus with a lod score of -4.14 for the penetrance of 0.72 and with a lod score of -3.05 for the lower bound penetrance of 0.56. The area of exclusion (lod score, less than -2.00) extended 27 centimorgans. These results provide strong evidence against linkage of the D2 dopamine receptor gene region to schizophrenia in the two pedigrees investigated. We conclude that the genetic predisposition to schizophrenia in these pedigrees is not due to aberrations in the DRD2 locus or the porphobilinogen deaminase locus. Our results do not support the D2 dopamine receptor hypothesis of schizophrenia. However, they cannot exclude the possibility that other genes regulating aspects of D2 dopamine expression might be involved in the etiology of schizophrenia, such as the expression of two D2 dopamine receptor subtypes by alternative RNA splicing.

California↗
PubMed1991

Correction of non-24-hour sleep/wake cycle by melatonin in a blind retarded boy.

A 9-year-old, blind boy with severe mental retardation with a chronic sleep/wake disturbance had a circadian rhythm of 24.75 hours and an internal desynchronization of the endogenous rhythms. Treatment with oral melatonin given at 6 PM induced a regular sleep/wake pattern. Melatonin, in this patient, convincingly entrained the endogenous rhythm to the appropriate chronological 24-hour day.

Blindness↗
PubMed1991

Clinical polydiagnostic studies in a large Swedish pedigree with schizophrenia.

A polydiagnostic computerized diagnostic system for psychosis was used in a Swedish family complex, and 51 patients with psychiatric symptomatology were examined with eight main diagnostic systems for schizophrenia and three systems for schizophrenic subgroups. All patients fulfilled the criteria for schizophrenia according to Taylor et al., 50 according to Carpenter, 41 according to RDC, and 31 of the 51 according to DSM-III and DSM-III-R. The hypothesis that the patients in the Swedish family complex differ from other phenotypes of schizophrenia must be refuted based on the data of the present study.

Adult↗