Cytochalasin B potentiates epinephrine’s outflow facility-increasing effect.

Kaufman Lab // Publications // Apr 01 1991

PubMed ID: 2016142

Author(s): Robinson JC, Kaufman PL. Cytochalasin B potentiates epinephrine’s outflow facility-increasing effect. Invest Ophthalmol Vis Sci. 1991 Apr;32(5):1614-8. PMID 2016142

Journal: Investigative Ophthalmology & Visual Science, Volume 32, Issue 5, Apr 1991

Total outflow facility was determined in both eyes of cynomolgus monkeys by two-level constant pressure perfusion. After a baseline measurement, one eye of the experimental animal received intracameral cytochalasin B (CB); the other eye received vehicle without CB. Twenty minutes later both eyes received intracameral epinephrine (EPI), and 30 min later the outflow facility was again determined. Doses of CB and EPI which were subthreshold when given singly produced significant facility increases when given concurrently. Subthreshold doses of CB given concurrently with a maximal dose of EPI produced significantly larger facility increases than a maximal dose of EPI given alone. A maximal dose of CB produced a larger facility increase than a maximal dose of EPI. Maximal doses of CB and EPI given concurrently produced a larger facility increase than did a maximal dose of EPI alone and had about the same effect as a maximal CB dose given alone. Since CB’s facility-increasing effect is likely due to “disruption” of actin filaments in the endothelial cells of the trabecular meshwork and Schlemm’s canal and since CB potentiates the facility-increasing effect of EPI, EPI may also act by “disrupting” actin filaments and consequently altering endothelial cell shape.