Natriuretic peptide system in the XXXX retina.

@entity1 @entity2194 @entity21695 @entity6 @entity13380 @entity3876 @entity726 @entity15580 @entity21694
PURPOSE: The natriuretic peptide (NP) family includes atrial natriuretic peptide (ANP), @entity3876 ( @entity3876 ), and @entity21695 ( @entity21695 ). Natriuretic peptides are known to inhibit vascular cell growth and regulate vessel tone. There is also much evidence to suggest they modulate vascular permeability and angiogenesis, as well as regulating aqueous humor production in the eye. All these data indicate that the natriuretic peptide system might be involved in the development of @entity6 and @entity726 . Given the expression pattern of natriuretic peptides (NPs) and their receptors, @entity13380 ( @entity13380 ), @entity21694 ( @entity21694 ) and @entity15580 ( @entity15580 ) in the @entity1 retina has not yet been established, the present study was designed to determine ANP, @entity3876 and @entity21695 gene expression and localize the mature peptides in this tissue. The expression pattern of the genes encoding the different NP receptor subtypes was also examined. METHODS: Eyes (n=10) from @entity1 donors with no history of @entity2194 were fixed and processed for routine paraffin embedding. The cellular location of the NPs was established by immunohistochemistry. Real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate the expression of NP and NP receptor genes in neural retinas obtained from the contralateral eyes. RESULTS: Immunohistochemistry revealed the presence of NPs in the neural retina and retinal pigment epithelium. Positive NP immunostaining was observed within the astrocytes and in their processes enveloping vessels. In the anterior portion of the optic nerve, NPs were intensely labeled in neural bundles. We were able to detect NP gene expression in the @entity1 retina. The levels of NP receptor-encoding transcripts detected indicated no significant differential expression of genes coding for the different receptor subtypes. CONCLUSIONS: Our finding that NP receptor transcripts are expressed along with ANP, @entity3876 , and @entity21695 mRNA in the @entity1 retina provides evidence for a local system in this tissue. The expression of NPs in neural retinal, glial, and vascular elements of the normal adult retina suggests a role for these peptides in maintaining both the neural and vascular integrity of the mature retina.
