Summary
The vascular surface of the external layer of the median eminence is composed of neuronal and glial processes. Neuro-vascular contacts are supposed to be necessary for the release of hypophysiotropic neurohormones.
The present study confirms the hypothesis that the relative extent of neuro-vascular and glio-vascular contacts varies under different functional conditions of the tubero-hypophysial system. Morphometric analysis shows that in normal rats about 20% of the surface is lined by neuro-vascular contacts. After bilateral adrenalectomy the neuro-vascular contacts are enlarged to 40% whereas application of an extract of stalk-median eminence tissue is followed by a decrease of the neuro-vascular contacts to 15%. The implications of these results are discussed.
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A grant of the Landesamt für Forschung NRW is gratefully acknowledged.
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Wittkowski, W., Scheuer, A. Functional changes of the neuronal and glial elements at the surface of the external layer of the median eminence. Z. Anat. Entwickl. Gesch. 143, 255–262 (1974). https://doi.org/10.1007/BF00519869
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DOI: https://doi.org/10.1007/BF00519869