Abstract
Purpose :
Natriuretic peptides (NPs, including ANP, BNP and CNP) and their receptors (NPR1, NPR2 and NPR3) play important roles in cardiovascular, skeletal and other systems by activating transmembrane guanylyl cyclases and elevating intracellular cGMP levels. In the present study we used RNAscope technique to compare the difference in expression levels and localizations of NPRs mRNA in the eyes of different species (including mouse, rabbit, cynomolgus monkey, and human).
Methods :
Paraffin sections and/or cryosections of mouse, cynomolgus monkey, human and rabbit eyes were used for in situ hybridization assay (i.e. RNAscope®) to determine the natriuretic peptide and receptor expression. Manufacturers (Advanced Cell Diagnostics) instructions were followed for RNAscope® experiments. NPR1, 2, 3 and NPPA, NPPB, NPPC probes for different species were applied. Negative controls, e.g. DapB and positive probes or tissues (brain) were included.
Results :
In the mouse eye, NPR3 is broadly expressed in trabecular meshwork (TM), ciliary body (CB), sclera and retina, while NPR1 is only expressed in the sclera and TM. NPR2 is mainly expressed in the retina. The NPR peptides ANP, BNP and CNP are only found weakly in the CB and retina. In the cynomolgus monkey eye, NPR1 and 2 are found in the retina. NPR3 is mainly in the retina. In the human eye, NPR1, 2, 3 are highly expressed in TM, CB and retina. In the human eye, NPRs were found in the TM (NPR2>NPR1>NPR3), CB (NPR3>NPR2>NPR1), retina (NPR3, NPR2>NPR1), expressed in RGC, INL and ONL layers and choroid RPE (NPR2, 3). In the rabbit eye, NPRs expressed in the TM (NPR1, NPR2, NPR3), CB (NPR1, NPR2, NPR3), retina (NPR1, NPR2, NPR3) and choroid RPE (NPR1, NPR2).
Conclusions :
The natriuretic peptides and their receptors are present in ocular tissues of several species where they participate in regulation of IOP. Our results indicated that differential NPR expression level and patterns in eyes of different species may explain different patterns of biological responses observed upon activation of different NPR subtypes.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.