Topical administration of iganidipine, a new water-soluble Ca2+ antagonist, increases ipsilateral optic nerve head circulation in rabbits and cynomolgus monkeys.
OBJECTIVE
To evaluate the effects of topically administered iganidipine hydrochloride, a novel water-soluble Ca2+- channel blocker, on optic nerve head (ONH) circulation in Dutch rabbits and cynomolgus monkeys.


METHODS
ONH tissue blood velocity (NBONH) was determined using the laser speckle method. In rabbits, NBONH was measured for 90 minutes before and after a single iganidipine administration, or before and after twice-daily ad- ministrations for 21 days (0.03%). In monkeys, NBONH was measured before and after twice-daily administrations of iganidipine for 7 days (0.03 or 0.1%).


RESULTS
Iganidipine (0.03% solution) significantly increased NBONH by 8 to 10% in treated eyes after a single administration (p < 0.05) or by 18 to 35% after 7-, 14-, or 21-day twice-daily administration in rabbits (p < 0.05). In monkeys, 0.03% and 0.1% iganidipine significantly increased NBONH in treated eyes by 20 and 41% after 7-day (p < 0.05) twice-daily administration, respectively.


CONCLUSIONS
Topical iganidipine significantly increased ONH blood velocity in treated eyes.
Ishii
Kiyoshi
K
Eye Clinic, Saitama red Cross Hospital, 8-3-33 Kamiochiai, Chuo-ku, Saitama-si, Saitama 338-0001, Japan. ikiyo@nifty.com
Fukaya
Yasuhiro
Y
Araie
Makoto
M
Tomita
Goji
G
D000287:Administration, Topical; D000818:Animals; D001775:Blood Circulation; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D002121:Calcium Channel Blockers / Q000008:administration & dosage*; D005260:Female; D007429:Intraocular Pressure / Q000187:drug effects; D017078:Laser-Doppler Flowmetry; D008252:Macaca fascicularis; D008297:Male; D009883:Ophthalmic Solutions / Q000008:administration & dosage; D009898:Optic Disk / Q000098:blood supply*; D010879:Piperazines / Q000008:administration & dosage*; D011725:Pyridines / Q000008:administration & dosage*; D011817:Rabbits; D012995:Solubility; D014664:Vasodilation
D002121:Calcium Channel Blockers; D009883:Ophthalmic Solutions; D010879:Piperazines; D011725:Pyridines; C108540:iganidipine