Effects of acetylcholine and carbachol on bovine corneal endothelial cells in vitro.
OBJECTIVE
To assess the relative cytotoxicity of Miochol (1% acetylcholine and mannitol), Miostat (0.01% carbachol, sodium, potassium, magnesium, and calcium salts), and their individual components using in vitro models of bovine corneal endothelial cells (BCECs).


METHODS
Laboratories of the Departments of Ophthalmology and Physiology, The University of Texas Health Science Center, Houston.


METHODS
The study was divided into four experiments. Experiment 1 used a confluent model to compare the relative cytotoxicity of Miochol and Miostat on BCECs following short-term exposure. In Experiments 2, 3, and 4, the proliferation model (preconfluent BCECs) was used to detect the possible cytotoxicity of individual components in the commercial preparations of the miotics; i.e., the preconfluent BCECs were exposed to buffered salt solutions containing mannitol (1%, 3%, and 4%), acetylcholine (0.5%, 1%, and 2%), or carbachol (0.1%, 0.5%, and 1%) for 3 hours.


RESULTS
Confluent BCECs exposed to Miochol for 30 minutes underwent necrosis and degeneration, while those treated with Miostat did not show any morphological changes. None of the tested solutions except 2% acetylcholine and 1% carbachol caused observable changes in the nuclear densities of BCECs at 24, 72, 120, and 168 hours.


CONCLUSIONS
The major components of Miochol (acetylcholine and mannitol) were found to be nontoxic; the cytotoxicity of the preparation was possibly due to the lack of an appropriate balanced salt solution. These findings may influence the selection of a miotic for use during intraocular surgery.
Yee
R W
RW
Department of Ophthalmology, University of Texas Health Science Center, Houston 77030, USA.
Meenakshi
S
S
Yu
H S
HS
Wallace
G A
GA
Kozielec
G
G
D000109:Acetylcholine / Q000009:adverse effects*; D000818:Animals; D002217:Carbachol / Q000009:adverse effects*; D002417:Cattle; D002452:Cell Count / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D004338:Drug Combinations; D004728:Endothelium, Corneal / Q000187:drug effects* / Q000473:pathology; D008353:Mannitol / Q000009:adverse effects*; D008916:Miotics / Q000009:adverse effects*
D004338:Drug Combinations; D008916:Miotics; D008353:Mannitol; D002217:Carbachol; D000109:Acetylcholine