Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Re-epithelialization of 40 iatrogenic cornea ulcers produced in rabbits with iodine vapour burn were studied after topical administration of Betagan, Betoptic or Timoptic. At 24 hours there was no statistical difference in the wound healing rates among all the treated animal groups. At 48 hours, all the drug-treated groups were significantly different from the control group (p less than 0.05). There was no difference between the Betagan and Betoptic treated groups but the Timoptic-treated group was slower (p less than 0.05) than the Betoptic treated group, while the difference between the Timoptic and Betagan treated groups is not significant. At 72 hours the re-epithelialization rate of the Timoptic treated group was significantly slower than both the Betagan and Betoptic treated groups (p less than 0.05). By the 16th day following ulceration SEM examination revealed the Timoptic treated group had extensive epithelial cell desquamation, as well as hole formation and plasma membrane disruption. The Betagan treated corneas had mild superficial epithelial changes with loss of microvilli or slight desquamation. The Betoptic treated corneas were completely healed. In conclusion, Betagan is less toxic than Timoptic. Betoptic is the least toxic of the three drugs to regenerating rabbit corneal epithelium.
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PMID:Toxic effects of topically administered Betagan, Betoptic, and Timoptic on regenerating corneal epithelium. 324 71

Accommodation and pupil constriction result from parasympathetic stimulation from the Edinger-Westphal (EW) nucleus of the midbrain resulting in release of acetylcholine at the neuromuscular junctions of the ciliary muscle and iris. Cholinergic and adrenergic drugs can be applied topically to evaluate the effects on the pupil and accommodative system without input from the EW nucleus. This study is directed at characterizing how topical low dose echothiophate, an anti-cholinesterase inhibitor (i.e., an indirect cholinergic agonist), epinephrine, an adrenergic agonist, and timolol maleate, a beta adrenergic antagonist, affect pupil diameter, resting refraction and accommodative amplitude and dynamics in rhesus monkeys. The effects of 0.015% echothiophate, 2% epinephrine, 0.5% timolol maleate and saline on pupil diameter and resting refraction were measured in one eye each of four normal rhesus monkeys for 60-90 min following topical instillation. Pupil diameter was measured with infrared videography and refraction was measured with a Hartinger coincidence refractometer. Effects on static and dynamic EW stimulated accommodation were studied in three iridectomized monkeys (ages 5, 6 and 12 years) with permanent indwelling stimulating electrodes in the EW nucleus. Dynamic accommodative responses were measured with infrared photorefraction for increasing current amplitudes before and during the course of action of the pharmacological agents. Echothiophate caused a significant decrease in pupil diameter of 3.07 +/- 0.65 mm (mean +/- SEM, p < 0.01), and a myopic shift in resting refraction of 1.30 +/- 0.39 D (p < 0.05) 90 min after instillation. Epinephrine caused a 2.76 +/- 0.38 mm (p < 0.01) increase in pupil diameter with no change in resting refraction 60 min after instillation. Timolol maleate resulted in no significant change in either pupil diameter or resting refraction 60 min after instillation. There was no significant change in maximum EW stimulated accommodative amplitude after any agent tested. The amplitude vs. peak velocity relationship for accommodation was significantly different after echothiophate and timolol maleate, and for disaccommodation after echothiophate, epinephrine and timolol maleate. In conclusion, when tested objectively in anesthetized monkeys, epinephrine and timolol maleate did not alter resting refraction or accommodative amplitude, but did have small, significant affects on accommodative dynamics. This suggests that there is an adrenergic component to the accommodative system. Low dose echothiophate had significant effects on pupil diameter and resting refraction, with only small effects on the dynamics of the accommodative response.
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PMID:Autonomic drugs and the accommodative system in rhesus monkeys. 1978 72