Effects of topical pre-treatment with dexamethasone on the immediate and late phases of topically induced ocular anaphylaxis in the rat.
We tested the effects of pre-treatment with dexamethasone on topically induced ocular anaphylaxis in the rat. Rats were immunized with dinitrophenylated Ascaris suum extract and challenged with di-DNP-lysine. Dexamethasone was administered topically once (24, 6, or 1 h before challenge) or three times (6, 4, and 2 h before challenge). A single pre-treatment given at 24 or 6 h had no significant effect. A single pre-treatment 1 h before challenge reduced the extent of edema assessed histologically but not clinically, and had no significant effect on the eosinophil count in conjunctival tissue examined 6 h after challenge. Eyes pre-treated with dexamethasone 6, 4, and 2 h before challenge showed a significant reduction in conjunctival edema assessed histologically and clinically 1 h after challenge. In addition, 6 h after challenge the number of eosinophils was significantly reduced. We conclude that repeated pre-treatment with dexamethasone can suppress both the immediate phase and the cellular late phase of topically induced ocular anaphylaxis.
Trocmé
S D
SD
Eye Research Institute of Retina Foundation, Massachusetts General Hospital, Boston.
Bonini
S
S
Barney
N P
NP
Bloch
K J
KJ
Allansmith
M R
MR
D000287:Administration, Topical; D000707:Anaphylaxis / Q000139:chemically induced*; D000818:Animals; D003907:Dexamethasone / Q000008:administration & dosage*; D005123:Eye / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
D003907:Dexamethasone