Serum proteins and aqueous outflow resistance

Tuesday, Sep 22, 1992 La PalmalA

X ICER Abstracts AQUEOUS HUMOR DYNAMICS

CODE: AH-I oJJ=Low

SEPTEMBER ZVTUESDAY SERUM PROTRINS AND M&Jobn~‘.If8i~GOllR*.-Raddoad~~’

I:-

ELKE LUTJEN-DRECOLL MICHAEL WIEDERHOLT

(GERMANY) (GERMANY)

1

9:oo

Serum Proteins and Aaueous Outflow Resistance M. Johnson, H. Gong, T. Freddo and R. Kamm (USA)

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9:18

Reeional Differences in Primarv Ooen An& Glaucomatous C. Flugel. M. Wiesand, E. Lutjen-Drecoll and D. Johnson (Germany)

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9:36 DV of the Human A.W. de Kater and R.R. Allingham The Juxtacanalicular hydLpdvnamic ~nstituents C.G. Murphy

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10:12

mt

02118

entering the ‘I34 may be much higher than tinding,wehaveeonduetedperfusienaad deterrnine(i)thceffcctof~~onMldbar~y~inthbovinteyes,and (ii)thedism'butionofsarrm~~iahe~~OUdbWBlthWly. Wefou~Ithatin fivepair~ofenuclutcdbaviaaeyes,~~~~'rate(thc pm~ssiveincnzase inoutflowfaeil~fhatoa3Fawhenwm-b~eytsare experimentally perfused) was invariably higher in the eye per&@

-TATION

9:54

RESISTANCE

LA PALMAlA

CHAIRPERSONS:

4

OUTFLOW

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HOTEL/ROOM:

NUMBER=

AQUROLIS

(USA)

Tissue in Piemcntarv

role of gtgment

with the lower serum protein concentration. At a serum wncentradon of lo-12%. lhe “wash-out” phenomenon could be entirely eliminated ‘llte results suggest that the “wash-out” phenomenon is due to a prognssive decrease in the levels of plasma-derived proteins entering the TM. Using monoclonal antibodies, we detexmi& the distribution of bovine senm~ albumin in unperfused bovine eyes, and in eyes pe&sed with concentrations of bovine serum tanging from O-15%. After pmbngcd perfusion with protein-free buffer, the amount of serum albumin in the TM, iris and ciliary body was substantially decxased. However, aftex perfusion with 515% suu&, the concennation of albumin in tbe TM, iris and eilii body WBSsimilar to unperfused conaol eyes. The highest -m&on of scnun &umin in the TM was found near Schlemm’s canal in the juxracanalicular connective tissue. Our results suggest that plasmaderlved proteins may play a role in the normal maintenance of aqueous outflow resistance.

and

and other

(USA) lOl-SWldromc:

” of a SV U. Schlotzer-Schrehardt, M. Koca and G.O.H. Naumann (Germany)

220

2

REGIONAL DIFFERENCES IN PRIMARY OPEN ANGLE GLAUCOMATOUS EYES Fliiqel, C., Wiesand, M., Liitjen-Drecoll, E. and Johnson, D.* Erlangen-Nilrnberq, FIX., Dept. of Anatomy, Univ. *Dept. Ophthalmology, Mayo Clinic, Rochester, IJSA The outflow suffering

tissue of 18 eyes from 9 donors (59-89 yrs) from primary open angle glaucoma and of 20 normal eyes from 10 donors (43-90 yrs) without history of eye disease were morphometrically analyzed and investigoted by electron microscopy. In contrast to normal eyes in the trabecular meshwork of the glaucomatous L:‘I~':~, marked regional differences were found concerning &tcnsion and width of Schlemm‘s canal as well as increase of extracellular material in the filtering portion of the meshwork. In some parts of the cirrumference, the trabecular meshwork "as very dense due to thickened and "glued" lamellae, and Schlemm‘s canal was collapn+l. In contrast, other parts were characterized by a loose trabecular meshwork showing optically "empty pathways" and a wide Schlemm‘s canal. Interestingly, in t11ese parts, the meshwork often appeared rarified with destroyed trabecular lamellae. This destruction of the connective tissue might be an effect of pharmacological treatment. The remaining underperfused parts of circumference undergo a vitious circle and become more dense and obstructed. These findings indicate that in contrast to the more evenly distributed aqueous pathways in normal eyes, in glaucomatous eyes only few preferential pathways remain.

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3 THREE.-DIMENSIONAL

CONFOCAL

LASER

SCANNING

MICROSCOPY

OF THE

HUMANTRABECULARMK%WORK -am. R.R. Dept. of Ophthalmology, UT Southwestern Medical Center at Dallas, Texas. The major site of resistance to aqueous humor outflow is thought to reside in the juxtacanalicular tissue (JCT) where aqueous humor filters through a meshwork of extracellular matrix (ECM) proteins. We are currently investigating the spatial distribution of ECM proteins and their relation with intracellular cytoskeletal proteins in normal and glaucomatous human eyes by confocal laser scanning microscopy. Indirect immunohistcchemical metbocls are used to label thick frozen sections with antibodies to fibroneedn (FN), laminin, collagen III, IV and V, and F-a&n. The specimens are examined with a BioRad MRC-600 or a Leica CLSM confocal laser scanning microscope. Serial images of the JCT are obtained and reconstructed with image restoration techniques on a Silicon Graphics 4D/240 GTX system. FN is oriented in discrete elongated patches subjacent to the inner wall of Schlemm’s canal, in a parallel orientation to the longitudiial axis of the endothelial cells. The patches of FN appear less dense at the basal opening of the giant vacuoles in the inner wall. Patches of FN also extend down toward the JCT to form connections between the inner wall cells and the underlying JCT cells. F-a&n is organized in a stress fiber-like configuration along the longitudinal axis of the inner wall cells and appears to be preferentially localized in the peripheral cytoplasm and at the base of the giant vacuoles. No apparent differences were noted between normal and glaucomatous eyes for either of these proteins. Further results on the distribution oflaminin, collagen III, IV and V will he presented.

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