Conjunctival provocation tests with codeine phosphate. Effect of disodium cromoglycate.
The reactivity of ocular mast cells is poorly characterized in man. Provocation tests with codeine phosphate, a molecule known to activate connective tissue mast cells, were performed in ten normal subjects. Ten-fold increasing concentrations of codeine phosphate (10(-5) to 10(-1) mg/mL) were tested in both eyes until a positive challenge was observed. Schirmer strips were placed under the eyelid and left for five minutes. A negative control was performed ten days later. All subjects had a strongly positive reaction for the same codeine phosphate concentration (10(-1) mg/mL). Histamine was released in 8/10 subjects (control: 7.06 +/- 4.19 nM/L, codeine phosphate: 18.2 +/- 15.7 nM/L, P < .018), PGD2 was released in 8/10 subjects (control: 0 codeine phosphate: 273.3 +/- 408.9 ng/L). Disodium cromoglycate blocked the release of histamine and PGD2. Codeine phosphate is potent at causing mast cell activation in the eye and this effect is blocked by disodium cromoglycate.
Campbell
A M
AM
Clinique des Maladies Respiratoires, Montpellier, France.
Demoly
P
P
Michel
F B
FB
Bousquet
J
J
D000328:Adult; D003061:Codeine / Q000008:administration & dosage* / Q000037:antagonists & inhibitors; D003228:Conjunctiva / Q000166:cytology / Q000187:drug effects*; D003231:Conjunctivitis / Q000175:diagnosis; D004205:Cromolyn Sodium / Q000494:pharmacology*; D006636:Histamine Release; D006801:Humans; D008407:Mast Cells / Q000187:drug effects / Q000502:physiology; D015230:Prostaglandin D2 / Q000378:metabolism
D004205:Cromolyn Sodium; D015230:Prostaglandin D2; D003061:Codeine