Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:1.6.5.4 (
SOR
)
720
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Ocular injury in the rabbit causes miosis and breakdown of the blood aqueous barrier (aqueous flare response,
AFR
), reflecting a sensory nerve-mediated inflammatory response, elicited by the release of tachykinins and calcitonin gene-related peptide (CGRP) from C-fibers.
Neuropeptide Y
(
NPY
) occurs in sympathetic fibers in the eye. The study was designed to examine whether
NPY
and related peptides interfere with the inflammatory response to ocular injury in the rabbit in vivo. The isolated rabbit iris was studied with respect to
NPY
binding sites and second messenger coupling. The
AFR
and the miotic response to a standardized injury (infrared irradiation (IR) of the iris) were suppressed dose-dependently by
NPY
(0.01-1.0 nmol) injected intravitreally 30 min prior the trauma. The treated eye was compared with the contralateral eye, which received 0.9% saline and IR. The Y1 receptor agonist [Pro34]
NPY
, the Y2 receptor agonist
NPY
13-36 and the structurally related peptide YY (1 nmol each) suppressed the
AFR
in response to IR. Injection of either
NPY
or the Y1 and Y2 receptor agonists (0.3 nmol each) suppressed the
AFR
evoked by exogenously applied CGRP (0.15 nmol). Saturation studies with 125I-
NPY
revealed both high and 'moderate' affinity binding sites in the iris. The Bmax values were 26 and 321 fmol/mg protein, respectively.
NPY
suppressed the forskolin-stimulated adenylate cyclase activity (IC50 value 19 nM).
NPY
did not affect basal or noradrenaline-induced accumulation of inositol phosphates in the iris. In conclusion, the rabbit iris seems to be rich in
NPY
receptors linked to inhibition of adenylate cyclase activity.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Neuropeptide Y suppresses the neurogenic inflammatory response in the rabbit eye; mode of action. 838 Dec 38