61 research outputs found
Endogenous opioid peptides and epilepsy
In recent years a large number of pept:ides, many of which were
originall.y characterized in non-neural tissues, have been reported to be
present in the central nervous system ( CNS) . The detection of these
peptides within the CNS has raised many questions regarding their source
and mechanism of action.
In view of the accumulating information, it seems that the function of the
classical neurotransmitters in the CNS would be better clarified by
elucidating the role of the brain neuropeptides.
The classification of the major categories of the main peptides, as listed
below, is a some what arbitrary one as it is based on the first
localization of a given peptide, while the opioid peptide family is given
separately. For many of the peptides described in brain, their major
functional role is still unknown. However, even before the major
discoveries in the past decade, the opiates were known to possess selective
and unique pharmacological properties. It was well known that opiates were
effective in the treatment of pain and were useful as cough suppressants.
They are also known to depress respiration and blood pressure and to exert
an effect on behaviour, like euphoria, sedation and depression. The
diversity/complexity of their properties suggests that like the
catecholamines, endogenous opioids may have a basic, multisystem regulation
essential to the maintenance of homeostasis and to the survival of the
organism.
In the last years we have tried to reveal one of these petidergic secrets
and focussed our attention on the opioid pe~ides, more specifically in
relation to the excitatory phenomena which they might induce after systemic
or intraventricular administratio
Prediction of Mental Health Services Use One Year After Regular Referral to Specialized Care Versus Referral to Stepped Collaborative Care
FSW - Self-regulation models for health behavior and psychopathology - ou
Serum BDNF Concentrations Show Strong Seasonal Variation and Correlations with the Amount of Ambient Sunlight
Contains fulltext :
109494.pdf (publisher's version ) (Open Access)Earlier findings show seasonality in processes and behaviors such as brain plasticity and depression that in part are regulated by Brain-Derived Neurotrophic Factor (BDNF). Based on this we investigated seasonal variation in serum BDNF concentrations in 2,851 persons who took part in the Netherlands Study of Depression and Anxiety (NESDA). Analyses by month of sampling (monthly n's >196) showed pronounced seasonal variation in serum BDNF concentrations (P<.0001) with increasing concentrations in the spring-summer period (standardized regression weight (ss) = 0.19, P<.0001) and decreasing concentrations in the autumn-winter period (ss = -0.17, P<.0001). Effect sizes [Cohen's d] ranged from 0.27 to 0.66 for monthly significant differences. We found similar seasonal variation for both sexes and for persons with a DSM-IV depression diagnosis and healthy control subjects. In explorative analyses we found that the number of sunshine hours (a major trigger to entrain seasonality) in the week of blood withdrawal and the 10 weeks prior to this event positively correlated with serum BDNF concentrations (Pearson's correlation coefficients ranged: 0.05-0.18) and this could partly explain the observed monthly variation. These results provide strong evidence that serum BDNF concentrations systematically vary over the year. This finding is important for our understanding of those factors that regulate BDNF expression and may provide novel avenues to understand seasonal dependent changes in behavior and illness such as depression. Finally, the findings reported here should be taken into account when designing and interpreting studies on BDNF
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