PRELYMPHATIC PATHWAYS OF BRAIN AS REVEALED BY CERVICAL LYMPHATIC OBSTRUCTION AND PASSAGE OF PARTICLES

  • 1 January 1976
    • journal article
    • research article
    • Vol. 57  (2) , 179-188
Abstract
Light microscopy and EM were used to examine portions of the brain, the circle of Willis and the internal carotid arteries of normal cats and rabbits, of sham-operated ones and of those whose cervical lymphatics were ligated. Carbon was injected into the cerebral cortex of some lymphedematous animals. Lymphatic ligation produced edema of the brain, and a dilatation of the prelymphatic spaces around the vessels. Carbon was traced in these from the injection site, around the minor and major vessels, in the adventitia of the internal carotid artery, entering lmphatics adjacent to it and finally in the draining lymph nodes. The edema and dilated spaces were not present in the control animals. There was a continuous system of non-endothelialized spaces and potential spaces, the prelymphatics, draining the brain into the cervical lymphatics. The protein in these spaces appeared to be increased if the lymphedema lasted 3 wk as compared to 24 h, indicating that one of the major roles of this system is the removal of protein.