Measurement of activities in two different angiotensin II generating systems, chymase and angiotensin-converting enzyme, in the vitreous fluid of vitreoretinal diseases: a possible involvement of chymase in the pathogenesis of macular hole patients.
OBJECTIVE
To investigate possible involvement of chymase and angiotensin-converting enzyme (ACE) in the pathogenesis of vitreoretinal diseases, both of which are related to the production of angiotensin II.


METHODS
We measured chymase and ACE activities in the vitreous in the 54 affected eyes of 54 patients who had undergone vitreous surgery for idiopathic macular holes (MH, n = 14), proliferative diabetic retinopathy (PDR, n = 14), idiopathic epiretinal membranes (ERM, n = 13), and rhegmatogenous retinal detachment (RRD, n = 13).


RESULTS
Chymase activities in the vitreous from patients with MH, PDR, ERM, and RRD were 1.87 +/- 0.53, 0.06 +/- 0.04, 0.40 +/- 0.12, and 0.08 +/- 0.03 (mean +/- SE) mU/mg protein, respectively, and ACE activities in the vitreous humor were 0.18 +/- 0.09, 0.30 +/- 0.07, 0.01 +/- 0.01, and 0.03 +/- 0.02 (mean +/- SE) mU/mg protein, respectively. Chymase activity was significantly elevated in MH among these diseases (p < 0.01, Scheffe), and ACE was significantly activated in PDR compared to ERM and RRD (p < 0.05, Scheffe).


CONCLUSIONS
Our results suggest that two different angiotensin II generating systems are activated in human vitreous humor; an increased activity of chymase may play a possible role in the formation of macular holes.
Maruichi
M
M
Department of Ophthalmology, Osaka Medical College, Osaka 569-8686, Japan.
Oku
H
H
Takai
S
S
Muramatsu
M
M
Sugiyama
T
T
Imamura
Y
Y
Minami
M
M
Ueki
M
M
Satoh
B
B
Sakaguchi
M
M
Miyazaki
M
M
Ikeda
T
T
D000368:Aged; D000804:Angiotensin II / Q000378:metabolism*; D053818:Chymases; D003930:Diabetic Retinopathy / Q000201:enzymology; D004789:Enzyme Activation; D019773:Epiretinal Membrane / Q000201:enzymology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*; D012163:Retinal Detachment / Q000201:enzymology; D012167:Retinal Perforations / Q000201:enzymology* / Q000209:etiology; D012697:Serine Endopeptidases / Q000378:metabolism*; D014821:Vitrectomy; D014822:Vitreous Body / Q000201:enzymology*
D000804:Angiotensin II; D007703:Peptidyl-Dipeptidase A; D012697:Serine Endopeptidases; D053818:Chymases