Do antiglaucomatous prostaglandins induce melanogenesis in human conjunctiva?: an impression cytology pilot study.
OBJECTIVE
To determine the effect of antiglaucomatous prostaglandin analogs on conjunctival melanogenesis.


METHODS
For this pilot study, 30 glaucomatous patients treated with prostaglandin drops (alone and in association to beta-blockers) and 30 control subjects (15 healthy volunteers and 15 patients treated with beta-blockers) were included in this transversal, single masked, case-control, observational study. Skin complexion, eye color, conjunctival pigmentation, lacrimal tests, and corneal fluorescein staining were evaluated. Immunoreactivity for Tyrosinase was assayed on conjunctival imprints.


RESULTS
Twenty percent of patients treated with prostaglandins and 10% of the control subjects clinically manifested conjunctival pigmentation (P=0.279). Only 4% (8/198) of the conjunctival specimens were positive to Tyrosinase immunostaining, with no statistically significant difference among the groups (P=0.449). In all cases, the proportion of positive cells was below 4%. When compared with subjects having negative specimens, those with positive immunostains did not show any statistically significant difference in skin complexion, eye color or exposure to irritants, and ultraviolet (P>0.05).


CONCLUSIONS
According to our preliminary results, prostaglandin antiglaucomatous analogs do not significantly enhance pigmentation in the superficial layers of the conjunctiva. The existence of the Tyrosinase enzyme in the superficial layers of the conjunctiva suggests that basal melanocytes may transfer their melanogenic apparatus to superficial epithelial cells.
Cagigrigoriu
Andrea
A
Department of Ophthalmology, San Luigi Hospital, Italy.
Boero
Elena
E
Carenini
Alessandra Boles
AB
Rolle
Teresa
T
Cappia
Susanna
S
Bacillo
Elisa
E
Papotti
Mauro
M
Gregori
Dario
D
Brovarone
Filippo Vitale
FV
Grignolo
Federico Maria
FM
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage; D000368:Aged; D000959:Antihypertensive Agents / Q000008:administration & dosage*; D016022:Case-Control Studies; D003228:Conjunctiva / Q000187:drug effects* / Q000378:metabolism; D004359:Drug Therapy, Combination; D005127:Eye Color; D005260:Female; D005901:Glaucoma / Q000188:drug therapy / Q000378:metabolism; D006801:Humans; D008297:Male; D008543:Melanins / Q000378:metabolism*; D008544:Melanocytes / Q000187:drug effects / Q000378:metabolism; D008875:Middle Aged; D014442:Monophenol Monooxygenase / Q000378:metabolism; D009883:Ophthalmic Solutions / Q000008:administration & dosage; D010865:Pilot Projects; D011461:Prostaglandins F, Synthetic / Q000008:administration & dosage*; D016037:Single-Blind Method; D012880:Skin Pigmentation
D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents; D008543:Melanins; D009883:Ophthalmic Solutions; D011461:Prostaglandins F, Synthetic; D014442:Monophenol Monooxygenase