ISSN:
1432-0878
Keywords:
Nervous System
;
Carcinus maenas
;
Cerebral ganglion
;
Intracerebral capillaries
;
Electron microscopy
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary The structure of the cerebral ganglion of the shore crab, Carcinus maenas, is investigated by conventional electron miscroscope techniques, with particular emphasis on the relation of intracerebral blood vessels to other elements in the brain. The ganglion is permeated by a continuous network of channels which may be interpreted as invaginations of the ganglion surface. The afferent vessel (cerebral artery) is of mesodermal origin, but apparently terminates as an open-ended vessel soon after entering the brain, where it runs within the invaginated channels. The greater part of the cerebral vasculature, therefore, has no mesodermal endothelial lining. Tissue components in the diffusion path between blood and brain which could conceivably restrict diffusion, are the thick glial basement membrane, junctions between perivascular and between interstitial glia, and polymeric material in the extracellular space. However, apart from a barrier to large colloidal particles at the basement membrane, the present EM observations do not decisively pinpoint sites of diffusional restriction, nor can they be interpreted as evidence that such restriction exists.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00324900
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