The effects of subconjunctival verapamil on filtering blebs in rabbits.
OBJECTIVE
Verapamil is a calcium antagonist that has been shown to modulate wound healing through multiple mechanisms. The wound modulating effects of verapamil were studied in a rabbit model of filtering surgery.


METHODS
Twenty New Zealand albino rabbits underwent a fistulizing procedure, with either verapamil or saline injected subconjunctivally daily for 6 days following surgery. The animals were sacrificed at 20 days after the fistulizing procedure. The effectiveness of verapamil in modulating wound healing was evaluated by bleb patency testing, histology, measurement of scar thickness, and counts of bromodeoxyuridine (BrdU)-labeled cells at the sclerostomy site.


RESULTS
The group treated with verapamil had a 44 percent patency rate compared with 10 percent in the control group (P < .05), a mean scar thickness of 195.96 +/- 68 mu m compared with 313.55 +/- 110.4 mu m in the control group (P < .02), and a mean BrdU-labeled cell count of 15.5 +/- 14.7 compared with 26.3 +/- 17.0 in the control group (P < .002).


CONCLUSIONS
Verapamil was effective in reducing scar formation at the sclerostomy site. At the doses administered, verapamil appeared to modulate wound healing in filtering blebs in the rabbit model. Further studies are needed to determine the dose-response and the efficacy of the drug in nonhuman primates.
Gupta
B
B
Department of Ophthalmology, Eye and Ear Infirmary, University of Illinois at Chicago, Ill, USA.
Agarwala
A
A
Moy
J J
JJ
Edward
D P
DP
D000818:Animals; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000494:pharmacology*; D002455:Cell Division; D003228:Conjunctiva; D004261:DNA Replication / Q000187:drug effects; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005500:Follow-Up Studies; D007267:Injections; D011817:Rabbits; D012590:Sclera / Q000187:drug effects* / Q000473:pathology; D012599:Sclerostomy; D016896:Treatment Outcome; D014700:Verapamil / Q000008:administration & dosage / Q000494:pharmacology*; D014945:Wound Healing / Q000187:drug effects
D002121:Calcium Channel Blockers; D014700:Verapamil