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The lymphatic vascular system of the mouse head

View Article: PubMed Central - PubMed

ABSTRACT

Histological studies of the lymphatic vascular system in adult mice are hampered because bones cannot be sectioned properly. Here, we decalcified the heads of 14-day-old mice, embedded them in paraffin and stained resultant serial sections with the lymphendothelial-specific antibodies Lyve-1 and Podoplanin. We show that the tissues with the highest lymphatic vascular density are the dermis and the oral mucous membranes. In contrast, the nasal mucous membrane is devoid of lymphatics, except for its most basal parts below the vomeronasal organ. The inferior nasal turbinate contains numerous lymphatics and is connected to the nasolacrimal duct (NLD), which is ensheathed by a dense network of lymphatics. The lymphatics of the eye lids and conjunctiva are connected to those of the inferior nasal turbinate. We suggest that cerebro-spinal fluid (CSF) can drain via the optic nerve and NLD lymphatics, whereas CSF drained via the Fila olfactoria into the nasal mucous membrane is used for moisturization of the respiratory air. Tongue, palatine and buccal mucous membranes possess numerous lymphatics, whereas the dental pulp has none. Lymphatics are present in the maxillary gland and close to the temporomandibular joint, suggesting the augmentation of lymph flow by chewing and yawning. Lymphatics can also be found in the dura mater and in the dural septae entering into deeper parts of the brain. Our findings are discussed with regard to CSF drainage and potential routes for ocular tumor dissemination.

No MeSH data available.


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Lyve-1-positive lymphatics of the eye. a Overview showing the eye with the cornea (c), upper eyelid (uel) and lower eyelid (lel) and nasal cavity (nc). Magnification ×20. Bar 400 μm. b Higher magnification of a. Of note is the lymphatic network starting at the limbus of the cornea (c) and extending from the conjunctiva of the nicitating membrane (n) into the upper eyelid (uel). Magnification ×40. Bar 200 μm. c Medial angle of the eye and the nasolacrimal sac (nls), which discharges into the NLD and has a dense network of lymphatics. Magnification ×40. Bar 200 μm
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Fig5: Lyve-1-positive lymphatics of the eye. a Overview showing the eye with the cornea (c), upper eyelid (uel) and lower eyelid (lel) and nasal cavity (nc). Magnification ×20. Bar 400 μm. b Higher magnification of a. Of note is the lymphatic network starting at the limbus of the cornea (c) and extending from the conjunctiva of the nicitating membrane (n) into the upper eyelid (uel). Magnification ×40. Bar 200 μm. c Medial angle of the eye and the nasolacrimal sac (nls), which discharges into the NLD and has a dense network of lymphatics. Magnification ×40. Bar 200 μm

Mentions: In the eye, Schlemm’s canal has previously been identified as a lymphatic-like vessel (Aspelund et al. 2014; Kizhatil et al. 2014; D.-Y. Park et al. 2014; Ramos et al. 2007). Our staining shows that a Lyve-1-positive vessel is present in the limbus of the cornea and seems to be part of a lymphatic network of the conjunctiva, which also covers the murine nictitating membrane (Fig. 5a, b). Additionally, the eyelids contain a dense network of initial lymphatics. At the medial angle of the eye, these lymphatics form a continuum with the lymphatic networks accompanying the NLD towards the inferior nasal turbinate (Fig. 5c). Moreover, squamous epithelial cells, which appear to be homologous to the Tenon capsule of the human eye, are Lyve-1-positive.Fig. 5


The lymphatic vascular system of the mouse head
Lyve-1-positive lymphatics of the eye. a Overview showing the eye with the cornea (c), upper eyelid (uel) and lower eyelid (lel) and nasal cavity (nc). Magnification ×20. Bar 400 μm. b Higher magnification of a. Of note is the lymphatic network starting at the limbus of the cornea (c) and extending from the conjunctiva of the nicitating membrane (n) into the upper eyelid (uel). Magnification ×40. Bar 200 μm. c Medial angle of the eye and the nasolacrimal sac (nls), which discharges into the NLD and has a dense network of lymphatics. Magnification ×40. Bar 200 μm
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC5121175&req=5

Fig5: Lyve-1-positive lymphatics of the eye. a Overview showing the eye with the cornea (c), upper eyelid (uel) and lower eyelid (lel) and nasal cavity (nc). Magnification ×20. Bar 400 μm. b Higher magnification of a. Of note is the lymphatic network starting at the limbus of the cornea (c) and extending from the conjunctiva of the nicitating membrane (n) into the upper eyelid (uel). Magnification ×40. Bar 200 μm. c Medial angle of the eye and the nasolacrimal sac (nls), which discharges into the NLD and has a dense network of lymphatics. Magnification ×40. Bar 200 μm
Mentions: In the eye, Schlemm’s canal has previously been identified as a lymphatic-like vessel (Aspelund et al. 2014; Kizhatil et al. 2014; D.-Y. Park et al. 2014; Ramos et al. 2007). Our staining shows that a Lyve-1-positive vessel is present in the limbus of the cornea and seems to be part of a lymphatic network of the conjunctiva, which also covers the murine nictitating membrane (Fig. 5a, b). Additionally, the eyelids contain a dense network of initial lymphatics. At the medial angle of the eye, these lymphatics form a continuum with the lymphatic networks accompanying the NLD towards the inferior nasal turbinate (Fig. 5c). Moreover, squamous epithelial cells, which appear to be homologous to the Tenon capsule of the human eye, are Lyve-1-positive.Fig. 5

View Article: PubMed Central - PubMed

ABSTRACT

Histological studies of the lymphatic vascular system in adult mice are hampered because bones cannot be sectioned properly. Here, we decalcified the heads of 14-day-old mice, embedded them in paraffin and stained resultant serial sections with the lymphendothelial-specific antibodies Lyve-1 and Podoplanin. We show that the tissues with the highest lymphatic vascular density are the dermis and the oral mucous membranes. In contrast, the nasal mucous membrane is devoid of lymphatics, except for its most basal parts below the vomeronasal organ. The inferior nasal turbinate contains numerous lymphatics and is connected to the nasolacrimal duct (NLD), which is ensheathed by a dense network of lymphatics. The lymphatics of the eye lids and conjunctiva are connected to those of the inferior nasal turbinate. We suggest that cerebro-spinal fluid (CSF) can drain via the optic nerve and NLD lymphatics, whereas CSF drained via the Fila olfactoria into the nasal mucous membrane is used for moisturization of the respiratory air. Tongue, palatine and buccal mucous membranes possess numerous lymphatics, whereas the dental pulp has none. Lymphatics are present in the maxillary gland and close to the temporomandibular joint, suggesting the augmentation of lymph flow by chewing and yawning. Lymphatics can also be found in the dura mater and in the dural septae entering into deeper parts of the brain. Our findings are discussed with regard to CSF drainage and potential routes for ocular tumor dissemination.

No MeSH data available.


Related in: MedlinePlus