IUBio

Dopamine dependent SAD

jonconx jonconx at MEblueyonder.co.uk
Tue Sep 26 15:35:53 EST 2000


I suffer from dopamine dependent Seasonal Affective Disorder.  In fall I
start to become depressed (this is characterized by hypersomnia and
paranoia).  This peaks in mid-winter and then fades out to become hypomania
in May.  This is now controlled with bromocriptine which is a dopaminergic
drug.  This is titrated against mood and used in the Fall and Winter months.
Starting out with just 1mg at the beginning of September and peaking with
30mg in the last couple of months of January.  This is then faded out to a
zero dose at the start of April .  Hypomania does not subsequently occur
with this treatment.

Small fluctuations in mood can occur with alcohol use, presumably as there
is dopamine release and a high when intoxicated and then a lack of dopamine
activity a few days later leading to depression and paranoia.  This resolves
within a couple of days.  Needless to say, I don't drink anymore and small
fluctuations in mood rarely occur.

I believe that with a lack of dopamine activity (i.e. in the winter) the
post-synaptic receptors become super-sensitive (dopamine hungry).  This
means they have a 'hair-trigger' and can fire inappropriatly.  In other
words there is noise in the system.  This leads to paranoid thinking and the
overall lack of activity leads to inactivity, hyposomnia and depression.  In
addition it could mean that adjacent receptors could fire inapproprately and
lead to thoughts which are not related clouding the issue and adding to
paranoid/psychotic thinking.  After a period of dopamine deprevation the
super-sensitive receptors can then 'over fire' when subjected to higher
levels of dopamine (e.g. in the spring).  This leads to hypomanic behaviour
with increased motor activity and mood which eventually settles down to a
normothymic condition (till the fall).

This can be backed up with by the action of dopaminergic drugs at different
stages of the disease process.  When there is normal mood (say july)with no
medication, the addition of dopaminergic drugs causes a slight lift in mood.
However, if thouroughly depressed and untreated(say January), the addition
of a dopaminergic drug produce profound mania in the short term due to
supersensitive post-synaptic receptors over -firing.  The receptors then
downregulate and normal mood is restored.

I wonder if anyone could answer the following questions:

Have other dopamine dependent conditions been described?

I there any validity in the above theory?

Does melatonin inhibit dopamine production? (producing seasonality)

Could this relate to seasonal control of dopamine synthesis and/or severe
receptor instability?

Are other psychotic disorders related to dysregulation of dopamine
receptors?

Is dopamine function related to immune function (if untreated, in mid-winter
I develop oral and nasal warts (yuk!) and developed such severe moluscum
contagiosum lesions one winter I was believed to have AIDS (I'm HIV
negative)

If antipsychotic drugs control schizophrenia, why do they block pre-synaptic
receptors and cause an overall increase in dopamine concentrations, could
they be working on above mechanisms?

Could bipolar 1 disorder be serotonin dependent and bipolar 2 disorder be
dopamine dependent?

Is human happiness as simple as a sole chemical and it's activity?

I am no neurobiologist, but if anyone could give me some guidence on the
above, I would be most grateful

Yours John Connelly
Birmingham, England

Email: jonconx at yahoo.com







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