1. Erythrocyte Nitric Oxide in Patients with glaucoma ex vivo study
Rita Esteves, Pedro Teixeira, Patrícia Napoleão, Carlos Neves, Carlota Saldanha
June 2016

2. Nitric Oxide – Vascular Tonus and Hemorrheology Regulator
After synthesis
Diffuses to erythrocytes
Diffuses to smooth muscle cells
Herrmann et al, European Heart Journal, 2010

3. Nitric Oxide is Scavenged by Erythrocytes
ACh
NO efflux
GSNO efflux
Timolol
less NO efflux
less GSNO efflux
Inibidor
Saldanha et al, J Clin Exp Ophtalmol, 2013
Carvalho et al, J Membrane Biol, 2009

4. Nitric Oxide and Glaucoma
Increased eNOS immunoreactivity in optic nerve head
Primary open angle glaucoma
Deregulation in ONH perfusion
Lesions in optic nerve/blindness
Overexpression of eNOS + nNOS
Decreased levels of cGMP and nitrite
Higher erythrocyte AChE activity
Alterations in L-arginine/NO system
Flemmer et al,Prog Retin Eye Res., 1998
Neufeld et al, Arch Ophtalmol, 1997
Polak et al, Arch Ophtalmol, 2007
Zabala et al, Eye (Lond), 1999

5. Nitric Oxide and Glaucoma
Treatment: timolol
IOP reduction
beta-adrenergic receptors antagonist
Inhibitor of erythrocyte AChE
(Zabala 1999)

6. Objective
Control
ACh
10-5 M
Timolol
Heparinized
venous blood
Healthy subjects
POAG patients
Determine timolol effect in erythrocyte nitric oxide efflux and its metabolites in POAG patients
NO efflux from erythrocyte
[GSNO] in erythrocyte

7. Erythrocyte Nitric Oxide: Healthy Subjects vs Glaucoma patients
Erythrocyte NO efflux in Healthy Subjects
Erythrocyte NO efflux in POAG Patients * *
N=18
N=15
Saldanha et al, J Clin Exp Ophtalmol, 2013

8. Erythrocyte Nitric Oxide: Healthy Subjects vs Glaucoma Patients
Healthy subjects (N=18)
Glaucoma patients (N=15)
*p<0,5 vs healthy subjects

9. Erythrocyte GSNO: Healthy Subjects vs Glaucoma Patients
Erythrocyte [GSNO] in Healthy Subjects
Erythrocyte [GSNO] in POAG Patients * * *
N=17
N=8

10. Erythrocyte GSNO: Healthy Subjects vs Glaucoma Patients
Healthy subjects (N=17)
Glaucoma patients (N=8)
*p<0,5 vs healthy subjects

11. Conclusions Erythrocyte of Glaucoma Patients vs Healthy Subjects
increased NO bioavailability
control
timolol
increased GSNO

12. Aknowledgements Carlota Saldanha Teresa Freitas Patrícia Napoleão
C. Saldanha Lab