A new study released in the Journal of the American Medical Association (JAMA) reported findings that supported the hypothesis that a medullary neurotransmitter, serotonin, may play a role in sudden infant death syndrome (SIDS).
The study was done in San Diego over the course of eight years, 1997-2005, and reviewed 31 cases of SIDS vs. ten control cases of neonatal death (one death was due to asphyxiation via a plastic bag…in other words some how a plastic bag was placed over a baby's head until the baby stopped breathing. Wow.)
There were statistically significant differences in regards to 5-hydroxytryptamine, 5-HT, or serotonin, neuron levels and 5-HT1a receptor-binding capacities in infants who passed due to SIDS vs. the control group. In the SIDS group, the infants had a larger amount of 5-HT neurons in the medulla oblongata, the brainstem center of the respiratory drive, and a lower 5-HT1a receptor binding capacity. The exact pathogenesis of how this contributes to SIDS has not been verified in the scientific literature and this study did not offer any exact pathological mechanism.
SIDS is certainly a topic in which people will listen and pay attention, but this study should not influence one to believe 5-HT is the cause of SIDS. Although this study supports 5-HT’s role in SIDS, the sample size was very small and the control group was far too low for accurate comparisons. The authors noted these limitations, as well as other more minute limitations, but nonetheless a study like this is important to drive future research on the relation between 5-HT and SIDS.
What the authors do suggest is a triple theory in which environmental stressors (lying in the prone position, on the baby’s belly, or bed-sharing), underlying vulnerabilities (5-HT abnormalities in the brainstem) and being less than six months old all contribute in the pathogenesis of SIDS. This study appears to support this “triple theory.”
Serotonin, or 5-HT, is an extremely popular neurotransmitter in medicine and modulating its function has become a mainstay of treatment for several diverse disease processes. Here is a brief review of some of them:
1. Depression – everyone has seen the commercial for sertraline (Zoloft), a selective serotonin reuptake inhibitor (SSRI), where the gloomy cloud refers to depression as a chemical imbalance in the brain due to serotonin deficiencies. SSRI’s are now one of the mainstays of depression treatment (with significant side-effects) and work by decreasing pre-synaptic reuptake of serotonin. The logic here is more 5-HT in the synaptic cleft, the area between two neurons, will lead to more stimulation in certain areas of the brain and elevate mood.
2. Schizophrenia – schizophrenics have what are called positive symptoms, i.e. hallucinations, and negative symptoms, i.e. depressed affect/mood. Older medications, referred to as typical neuroleptics, focused only on dopamine receptors and although they decreased the hallucination frequency, they had huge and life-threatening side-effect profiles and did not alleviate any of the depressive symptoms. The new class termed atypical neuroleptics is reported to have lower side-effect profiles (they really don’t) and work on both dopamine (D2) receptors as well as serotonin receptors (5-HT2a), thus theoretically erasing both positive and negative symptoms.
3. Migraine – the new standard of treatment for migrainous headaches revolve around prophylactic treatments, often with a beta-blocker or a tricyclic anti-depressant, and abortive therapies, such as the “tripitans”, i.e., sumatriptan (Imitrex). “Triptans” work on 5-HT2b and 5-HT2d receptors and cause vasoconstriction and decrease the vasodilatory effects, which elicit the pain during migraines.
4. Nausea/Vomiting – ondansetron (Zofran) is a drug that inhibits 5-HT3 receptors in the area postrema, an area of the brain involved in the vomiting reflex. These drugs are especially effective in decreasing vomiting after chemotherapy.
Those are the four that come to me without having to think. I am sure there are many more and serotonin will most likely be associated with other conditions.
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6 comments:
Are you trying to tell me something? I think I suffer from all four of your examples.
no. i just read about this article in the new york times. so i read the jama article. serotonin pops up all the time. i think you have migraines, but the others not so much. and i definently wouldn't recommend the psych meds. those are pretty evil at times.
i just think it's interesting how every field of medicine uses serotonin. i wasn't going to even post this, because it wasn't very good. i just thought i'd try to write about something medical since i haven't in awhile
if you don't stop putting yourself down i'm going to fly back to Michigan, cut off you balls and then board the next plane out with your nuts in my carry on.
all in the name of love, of course.
OK, maybe I am not schitzo. The rest apply.
whoa...please no castration. i don't know where i put myself down. i don't want to go into too much depth and i don't want to gloss over things, so i'm never sure if any of these things are really any good. but from now on no negativity.
jc, the nausea/vomiting and migraines i understand. and i also get the depression. it's hard not to be. you've had a rough year. but like we have both said it will get better. don't take any anti-depressants, but have faith in your friends and family. things will get better. i sound like a douche. sorry, but i really mean it.
and please, no one get sids
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