Circulation of the CSF

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Circulation of the CSF

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batman
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Topics: 9
Posts: 10

09/30/05 - 02:50 PM

Trace the circulation of the Cerebrospinal fluid. Begin with the process of secretion of CSF and end with return of CSF to the venous blood in the saggital sinus? I can't find this info. in my book. Thanks for the help!

sturge_weber
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Topics: 77
Posts: 1,042

09/30/05 - 10:38 PM

well it is secreted by the villi in the ventricle... so it starts from the lateral ventricle , reaches the third ventricle via the foramen of monroe, then from the third to the fourth ventricle via the aqueduct of sylvius, then from the fourth to the arachnoid granulations via the foramen of lushka and magendie{anyone of them} . from the arachnoid granulations in the subarachnoid space into the spinal cord

if there is block in formaens of luscka or magendie or munro, or aqueduct of sylvius, its non communicating hydrocephalus, if block in the arachnoid granulations, then communicating hydrocephalus

gpsbrar
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10/01/05 - 12:34 AM

C= CSF and C= Choroid plexus. Choroid p[lexus is the main producer and the next is the ependymal lining.

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mildus
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10/01/05 - 04:10 AM

I'd just like to add the mechanism of the CSF secretion. The CSF is produced from blood!
The blood vessels of choroid plexus are fenestrated capillaries, so plasma freely goes out from the capillaries into the interstitium and meets the ependymal cells which are connected by tight junctions (zonula occludens). So, the ependymal cells are those that don't permit plasma to go into the ventricles. They decide which substances they will let go into ventricles. There is an active transport of sodium from the interstitium to the venticles. Sodium is accompanied by Cl- and HCO3-, and they are followed by water. That is how CSF is produced. The most important proteins for this process are Na+/K+-ATPase and an enzyme called carboanhidrase.

sturge_weber
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10/01/05 - 07:03 AM

good mildus, keep it up

that was good info

sturge_weber
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Topics: 77
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10/01/05 - 07:06 AM

hey mildus and all, what happens to the csf after it passes thro arachnoid granulation, does it go spinal canal or ......

mildus
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10/01/05 - 11:13 AM

it goes into venous blood (sagittal sinus)

mildus
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Topics: 19
Posts: 614

10/01/05 - 11:19 AM

I don't think that the CSF goes from subarachnoid space to the spinal cord because there is no communication between subarachnoid space and central channel of the spinal cord. I would rather say that the CSF comes to the central channel of the spinal cord from the 4th ventricle.

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