A comparative study of topical natural ergot alkaloids on the intraocular pressure and aqueous humor dynamics in oclular normotensive and α-chymotrypsin-induced ocular hypertensive rabbits |
| |
Authors: | Gustavo Puras Juan Santafé José Segarra Manuel Garrido José Melena |
| |
Institution: | (1) Department of Pharmacology, Universidad Autónoma de Tamaulipas, Tamaulipas, Mexico;(2) Department of Pharmacology, Faculty of Pharmacy, Universidad del País Vasco, Vitoria, Spain;(3) Universidad Autónoma de Tamaulipas, Carretera Sendero Nacional Km 3., H-Matamoros, Tamaulipas, Mexico, 87349 |
| |
Abstract: | Background Although it has been suggested that ergot derivatives may play a role in antiglaucoma therapy, little attention has been paid
to the ocular hypotensive action of these drugs. Having previously reported that topical natural ergot alkaloids ergocristine
α-ergocryptine and ergocornine dose-dependently reduce intraocular pressure in ocular normotensive and α-chymotrypsin-induced
ocular hypertensive rabbits, the aim of the present work was to compare the effect of ergocristine, α-ergocryptine and ergocornine
on the intraocular pressure and aqueous humor dynamics in ocular normotensive and α-chymotrypsin-induced ocular hypertensive
rabbits, in order to further explore the ocular actions of these compounds.
Methods Experiments were conducted in albino ocular normotensive and hypertensive rabbits by intracameral injection of α-chymotrypsin.
Intraocular pressure responses to drug vehicle and seven different doses of topical natural ergot alkaloids were examined,
in order to obtain dose–response relationships for comparing the intraocular pressure-lowering effect and potency of these
drugs. Tonographies were also performed to ascertain the actions of natural ergot alkaloids on aqueous humor dynamics.
Results All natural ergot alkaloids tested reduced intraocular pressure in a dose-related fashion. The ocular hypotensive effect was
greater in α-chymotrypsin-induced ocular hypertensive rabbits for the three compounds tested. All natural ergot alkaloids
tested decreased both tonographic outflow facility and, to a greater extent, aqueous humor inflow in ocular normotensive and
in α-chymotrypsin-induced ocular hypertensive rabbits.
Conclusion Taken together, our data suggest that these compounds decrease both tonographic outflow facility and, to a greater extent,
aqueous humor inflow, which explains their final effect in ocular normotensive and in α-chymotrypsin-induced ocular hypertensive
rabbits. Reductions in aqueous humor inflow observed after topical application of natural ergot alkaloids in α-chymotrypsin-induced
ocular hypertensive rabbits can only be explained by a marked inhibition of active secretion of aqueous humor, since processes
involved in aqueous humor formation may probably be altered after α-chymotrypsin injection. |
| |
Keywords: | Intraocular pressure Ergot alkaloids Rabbits Aqueous humor dynamic |
本文献已被 SpringerLink 等数据库收录! |
|