Abstract
Abstract: :
Purpose: To investigate the effects of prostaglandin (PG) E1, E2, F2α and latanoprost on the electrically evoked contractile response of isolated rhesus monkey ciliary muscle. Methods: Ciliary muscle preparations from rhesus monkeys were mounted in an organ bath, and tension changes were recorded by an isometric transducer. Electrical field stimulation (100 Hz, 0.3 msec, 10 V) was applied through a pair of platinum plate electrodes. Results: The ciliary muscle produced atropine–sensitive excitatory contraction in response to field stimulation. PGE1 and PGE2 (1 µM) attenuated the contraction to levels that were 68% and 65.1%, respectively, of the normal amplitude. However, PGF2α and latanoprost (1 µM) did not significantly change the response amplitude. Conclusions: Our results indicate that PGF2α and latanoprost do not affect the prostanoid receptor involved at the pre– and/or post–synaptic site. Therefore, it is unlikely that the hypotensive action by these agents is due to relaxation of the ciliary muscle.
Keywords: ciliary muscle • pharmacology • outflow: ciliary muscle