Fower intensity was observed especially below the glia limitans (inner and outer) and in the neostriatum, and perineuronally in mesencephalic, cerebellar, and medulla oblongata nuclei.
Positivity was intense in choroid plexus cells, inner and outer glia limitans, and leptomeninges and was moderate in ependymocytes and the perivascular endfeet.
The glial components of the SO ventral zone that were vimentin-positive correspond to ventral glia limitans (Fig.
Ast=astrocyte, MCN= magnocell neuron, OC= optic chiasm, SO= supraoptic nucleus, VGL= ventral glial limitans.
A few studies, however, indicated for an alternative pathway of virus entry following direct intbction of microvascular endothelial cells of the blood brain barrier (31), Following entry the second step is getting past the glia limitans
(layer formed due to astrocytic end foot interdigitating with piamater along the surface and ependyma along the ventricles) which is an additional barrier both functionally and structurally.
The discovery of a specific autoantibody response in neuromyelitis optica (NMO) patients, which selectively targets astrocytic end feet at the glia limitans
(1) and which is directed against the water channel aquaporin-4 (AQP-4) (2) was a milestone in defining this disease entity and profoundly changed our view regarding its pathogenesis.
In the magnocellular neurosecretory system (MNS), CNTF is exclusively expressed in astrocytes of the supraoptic nucleus (SON), which are predominately located in the ventral glial limitans (VGL), and perivascular cells of the neurohypophysis.
Bobak, JB and Salm, AK (1996) Plasticity ofastrocytes of the ventral glial limitans subjacent to the supraoptic nucleus.
27] In theory, the perilymphatic trabecular meshwork and the membrana limitans should prevent, or at least minimize, the spread of streptomycin into the cochlea, thus preventing adverse effects to cochlear function.
It is also very likely that titration is made difficult by differences in individual patients' inner ear pathology, which might reduce the effect of the trabecular meshwork and membrana limitans.
Prions and their differences Characteristics Alpha normal prion(cPrP) Conformation 42% alpha; 3% beta ([alpha][greater than][beta]) Benign Yes Proteinase K Sensitive Accumulation Cell membrane of astrocytes Reservoir Produced naturally in the brains of all mammals; considered harmless Characteristics Beta infectious prion (sPrP) Conformation 43% beta, 30% alpha [beta][greater than][alpha] Benign No Proteinase K Resistant Accumulation Neurons in the medulla oblongata and pons of the glial brain limitans
Reservoir Produced from normal alpha prion proteins; confirmed as fatal Source: Prusiner SB.
The main target for the antibodies by IIF is the astrocytic foot processes that abut the abluminal surface of capillaries in the brain; they also bind along the subpial layer and at the glia limitans