Effects of betaxolol/timolol on epinephrine stimulated cyclic-AMP levels in human trabecular meshwork cells

@article{Polansky2005EffectsOB,
  title={Effects of betaxolol/timolol on epinephrine stimulated cyclic-AMP levels in human trabecular meshwork cells},
  author={Jon R. Polansky and Zvi Friedman and Donald J. Fauss and Ronald M. Irvine Kurtz and Jorge A Alvarado},
  journal={International Ophthalmology},
  year={2005},
  volume={13},
  pages={95-97}
}
The effects of timolol and betaxolol were compared for blocking beta agonist stimulation of cyclic-AMP in cultured human trabecular meshwork cells. Epinephrine (10−5 M) produced a large and rapid increase in HTM cyclic-AMP; timolol (10−6 M), at concentrations readily achieved in the aqueous humor after 0.5% eyedrops, completely blocked this effect. Recovery from timolol treatment appeared to be relatively slow, with only a 30–40% recovery observed by 9 hours. In comparison, betaxolol (10−6 M… 
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