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Blood - nerve barrier characteristics of research_2752

By Pamela Cox,2014-10-30 11:25
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Blood - nerve barrier characteristics of research_2752

Blood - nerve barrier characteristics of research

     Abstract The blood-ocular barrier with blood - aqueous

    barrier, the blood - retinal barrier, these special structure on the prevention of eye injury in the process of inflammation

    and immunity play an important role in the occurrence. To date, the blood - nerve barrier (blood-optic nerve barrier)

    the concept of domestic and foreign textbooks, almost no description, this article on the blood - nerve barrier

    characteristics of the study were reviewed.

     Key words blood - nerve barrier of blood - the blood-ocular

    barrier - brain barrier

     Research development of blood-optic nerve barrier

    characteristics

     * KEYWORDS: blood-optic nerve barrier, blood-ocular

    barrier, blood-brain barrier

     0 Introduction

     The eye is an organ immune privilege, there are several factors to maintain the special nature of the eye structure and function play a role, the most important is the blood-

    ocular barrier [1]. It can be useful for selective blood

    filtration material, in order to maintain a stable environment within the eye. When the barriers are harmful factors can affect its function during invasion, resulting in metabolic disorders, resulting in the occurrence of eye disease. Currently accepted blood-ocular barrier with blood - aqueous

    barrier, the blood - retinal barrier, these special structures on the prevention of eye injury in the process of inflammation and immunity play an important role in the occurrence. But so

far, right blood - nerve barrier (blood-optic nerve barrier)

    was highly controversial. Domestic and foreign textbooks, yet the concept. This article on the blood - nerve barrier

    characteristics of the study were reviewed.

     One blood - nerve barrier properties

     1963, Rodriquez-peralta [2] with 2-amino acridine dye

    injection method to observe the blood - nerve barrier

    characteristics of the situation. It was found that intravenous injection of 2-Amino-acridine appears in the optic

    nerve dura mater, but in the subarachnoid space and

    cerebrospinal fluid does not appear; in dural blood vessels, while in the soft meninges and blood vessels within the optic nerve does not appear; in choroid, sclera , Kuhnt tissue appears in the optic nerve did not appear. That the blood

    between the blood and optic nerve - optic nerve barrier

    properties. Barrier structure may be based on the optic nerve and pia mater capillary endothelial cells and their tight junctions.

     Two characteristics of the optic nerve

     Incoming visual information hub of the optic nerve is the only way is to treat the road from the optic nerve to the optic chiasm section. By retinal ganglion cells sent axons fiber drops, the histology of optic nerve and brain parenchyma in the white matter or spinal cord similar to the white

    matter. After the sieve surface, there is no Schwann optic nerve membrane, but there is myelin sheath. The optic nerve in the embryonic development of brain sticking out between the time of the formation of part of the course, as the device.

    There are 3 layers of optic nerve sheath, respectively, with the three-phase continuous layer of meninges. Inner layer of pia mater, the middle of the arachnoid, outer layer of dura mater. Optic nerve mainly consists of 4 above. (1) of the ball

    within a paragraph. (2) orbit segment. (3) The tube segment. (4), intracranial segment. The paragraphs blood supply is extremely complex. Sieve plate anterior optic nerve fibers without myelin sheath, and retinal nerve fibers within the same transparent, and therefore smaller; the sieve plate and sieve plate area after the myelin sheath surrounding the optic nerve fibers there and therefore I increase the thicker in diameter. Therefore, the optic nerve is not an ordinary

peripheral nerve, but central nervous ahead of a prominent

    nerve bundle.

     3 on the blood - nerve barrier properties of the

    controversy

     Since the Rodriquez-peralta in 1963 pairs of blood - to

    explore the characteristics of the optic nerve barrier since the domestic and foreign scholars of the in-depth study. In

    1970 Machemer [3] with alkaline rhodamine B labeled protein, intravenous injection, observed in the optic nerve and surrounding connective tissue are stained intervals, while the optic nerve did not stain. That there exists between the blood

    and optic nerve barrier properties. 1972, Peyman and Apple [4] with the electron microscope the distribution of horseradish peroxidase tracer was observed that there is no tracer into the optic nerve from the optic nerve capillary gap cavity.

    They believe in the existence of blood-brain barrier

    characteristics of the optic nerve. But their experiments did not mention whether the observed optic nerve head situation. Domestic scholars Yang Cun et al [5] that the blood vessels of the optic nerve with all the features of the central nervous system, blood vessels and performance of all of the peripheral capillary wall cells and surrounding cells, there is no gap between the endothelial cells and closely connected to the optic nerve microvascular bed is anatomically similar to the retina and central nervous system, blood vessels, and has self-regulation of physiological characteristics and blood-

    brain barrier performance. Made with the blood vessels within the optic nerve - optic nerve barrier performance. The barrier

    and the blood-brain barrier are very similar. The

    choriocapillaris around the optic nerve head does not have this barrier function, allowing free passage of blood substances big pore wall. 1975, Grayson and laties [6] After intravenous administration of fluorescein sodium, fluorescent material was observed around the optic nerve to the optic nerve from the spread. That the optic nerve and the lack of a close connection between the choroid from a structural point of view is not a complete barrier to keep only the physical barrier function. 2001, Hofman et al [7] the use of advanced blood-brain barrier, non-blood-brain barrier-specific marker

    of vascular permeability markers, combined with electron microscopy, pairs of optic nerve microvascular research. Found

    that the former area of optic nerve head capillaries lack of

blood-brain barrier properties, a weak blood-brain barrier-

    specific marker expression or no expression, endothelial cells were connected fenestrae-like cracks that contain many

    pinocytotic vesicles on the part of the plasma proteins with a transparent sex. The sieve plate area, sieve with a blood-

    brain barrier characteristics of the zone of capillary. Strong positive blood-brain barrier-specific marker expression,

    endothelial cell fenestrae-like and were not linked with fewer pinocytotic vesicles. Domestic scholars Amy [8] that the optic nerve head blood supply from the two systems, from the central retinal artery is a non-permeability of blood vessels

    associated with the choriocapillaris part of a certain

    material can be dispersed. Therefore, the blood - nerve

    barrier may belong to the blood - brain barrier part of the

    defect.

     4 blood - nerve barrier properties of research prospects

     Based on the current findings, the general view that does exist between the blood and the blood in the optic nerve -

    optic nerve barrier properties. Textbooks at home and abroad have not yet see the blood - the concept of the optic nerve

    barrier. Barrier structure may be based on the optic nerve and

    pia mater capillary endothelial cells and their tight junctions. Selective adoption of useful substances in the blood to maintain a relatively stable environment within the optic nerve. As for some of the small molecular weight tracer

    extravasation, in order to sieve the former area of blood -

    nerve barrier endothelial cell tight junctions between the bite was small with a small fracture sample, pinocytotic vesicles are more than just blood-brain barrier permeability

    increased due. However, for larger molecules with a barrier.