Peptide YY receptor distribution and subtype in the kidney: effect on renal hemodynamics and function in rats

Abstract

This study characterizes the location and subtype of peptide YY (PYY) receptors in rat and rabbit kidney and the effect of PYY on renal function and renal hemodynamics in rats. Receptor autoradiography performed on kidney sections revealed a dense concentration of specific high-affinity binding sites [dissociation constant ( K d) = 0.7 ± 0.1 nM] in the papilla of the rat, as well as cortical and papillary binding in the rabbit (papilla, K d = 1.6 ± 0.6 nM) and some medullary binding in both species. In the rat papilla, neuropeptide Y (NPY) and the Y1 agonist [Leu31, Pro34]NPY competed with PYY for binding ( K d = 1.1 ± 0.4 nM and 1.6 ± 0.5 nM, respectively), but NPY-(13—36) (Y2 agonist) and pancreatic polypeptide (PP, Y4 agonist) were without effect, demonstrating that the PYY receptor in the rat papilla is of the Y1 subtype. In the rabbit papilla, NPY and NPY-(13—36) competed with PYY ( K d = 0.5 ± 0.1 and 3.1 ± 0.6 nM, respectively), but [Leu31, Pro34]NPY and PP were without effect, evidence that the PYY receptor in the rabbit papilla is of the Y2subtype. Infusion of PYY into rats (47 pmol ⋅ kg−1 ⋅ min−1) increased mean arterial pressure (103 ± 6 to 123 ± 8 mmHg) and decreased renal plasma flow (13 ± 1.8 to 8.4 ± 2.1 ml/min) but produced no significant change in glomerular filtration rate or sodium excretion. Injection of PYY or angiotensin II directly into the renal artery caused a dose-related vasoconstriction, which was less intense but of longer duration for PYY than for angiotensin II. These results show that receptors for PYY are widely distributed in the kidney and that exogenously administered PYY causes renal vasoconstriction and may influence renal sodium excretion.

Recent Developments in Our Understanding of the Physiological Role of PP-Fold Peptide Receptor Subtypes

“…detected in area postrema with lower levels in the olfactory bulb and hippocampus (237). In the periphery, autoradiography studies using rat and rabbit kidney revealed that Y I is the predominant receptor subtype in the rat kidney, whereas Y2 is the predominant PP-fold receptor in rabbit kidney (238). Human adipose tissue contains a BIBP3226-sensitive receptor that bound 1251_[Leu31.Pro34]PYY and 1251_PYY and thus confirmed the presence of the Y I receptor and absence of Y2 in adipocytes (221).…”

Gut feedback mechanisms and food intake: a physiological approach to slow carbohydrate bioavailability

“…These receptors are distributed in a wide range of tissues and organs: PYY preferring binding sites in the crypt cells in the small intestine, 131 epithelial and nonepithelial tissues of the small or large intestine, 132 human gastrointestinal tract muscle cells, 133 differential and discrete distribution in the central nervous system, 134 pancreas for secretion inhibition, 135 human fat cells 136 for anti-lipolytic effects, the kidney for renal vasoconstriction and sodium excretion, 137 and ventricular arteries of heart. PYY show high affinity to all receptors, while only PYY shows high specificity to receptor Y2 that was considered as the major functional receptor mediating many processes.…”

The Renal Microcirculation

“…The kidney expresses NPY receptors, which can also be activated by peptide YY (PYY), a circulating hormone released from gastrointestinal cells. The vasoconstriction appears to be mediated by a calcium entry step, much like Ang II [105,106,1749,1750] . Administered NPY constricts both the afferent and efferent arterioles [1749] .…”