Purchase this article with an account.
J.G. Crowston, C.A. Morris, J.D. Lindsey, R.N. Weinreb; Circadian Intraocular Pressure in Prostaglandin FP Receptor Knock Out Mice . Invest. Ophthalmol. Vis. Sci. 2005;46(13):3793.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: The prostaglandin (PG) FP receptor is expressed in human ocular tissues. Topical application of PG F2a analogues that activate the FP receptor lower IOP and reduce circadian IOP fluctuation. It is, however, not known whether the FP receptor plays an important role in circadian regulation of intraocular pressure. The purpose of this study was to compare circadian IOP changes in FP receptor knockout mice with wild type mice that have normal FP receptor expression. Methods: IOP was measured using microneedle cannulation of the anterior chamber in homozygous (FP–/– n=8), heterozygous (FP+/–, n=14) C57BL/6 background strain mice (FP+/+, n= 11) at 8 am, 2 pm and 8 pm. The investigator was masked to the mouse genotype at the time of the measurement. To confirm any differences in baseline IOP between genotypes, mid–afternoon IOP was measured in a separate population of FP–/– mice (n=8) FP+/– mice (n=28) and FP+/+ (n=11) wild type litter mates. Results: There was no significant difference in IOP between genotypes at any of the three time points. Furthermore, there was no significant difference in the magnitude of circadian IOP variation between wildtype (mean+/–SEM, 1.82 mmHg +/– 0.6), FP+/– mice (2.7mmHg +/– 0.7) and FP–/– mice (2.7mmHg +/– 1.2). Further IOP measurement in a larger population of FP knockouts and wild type littermates confirmed no difference in afternoon IOP. Conclusions: There was n significant difference in baseline IOP or circadian IOP fluctuation between wild type and FP knockout mice. This indicates that the FP receptor does not play a critical role in circadian IOP regulation. Supported by NIH grant Ey005990
This PDF is available to Subscribers Only