Distribution of neuropeptide Y Y1 receptors in rodent peripheral tissues.
Using a sensitive immunohistochemical technique, the localization of neuropeptide Y (NPY) Y1-receptor (Y1R)-like immunoreactivity (LI) was studied in various peripheral tissues of rat. Wild-type (WT) and Y1R-knockout (KO) mice were also analyzed. Y1R-LI was found in small arteries and arterioles in many tissues, with particularly high levels in the thyroid and parathyroid glands. In the thyroid gland, Y1R-LI was seen in blood vessel walls lacking alpha-smooth muscle actin, i.e., perhaps in endothelial cells of capillaries. Larger arteries lacked detectable Y1R-LI. A distinct Y1R-immunoreactive (IR) reticulum was seen in the WT mouse spleen, but not in Y1R-KO mouse or rat. In the gastrointestinal tract, Y1R-positive neurons were observed in the myenteric plexus, and a few enteroendocrine cells were Y1R-IR. Some cells in islets of Langerhans in the pancreas were Y1R-positive, and double immunostaining showed coexistence with somatostatin in D-cells. In the urogenital tract, Y1R-LI was observed in the collecting tubule cells of the renal papillae and in some epithelial cells of the seminal vesicle. Some chromaffin cells of adrenal medulla were positive for Y1R. The problem of the specificity of the Y1R-LI is evaluated using adsorption tests as well as comparisons among rat, WT mouse, and mouse with deleted Y1R. Our findings support many earlier studies based on other methodologies, showing that Y1Rs on smooth muscle cells of blood vessels mediate NPY-induced vasoconstriction in various organs. In addition, Y1Rs in other cells in parenchymal tissues of several organs suggest nonvascular effects of NPY via the Y1R.
Department of Neuroscience, Karolinska Institutet, Retzius Laboratory, Retzius Väg 8, S-171 77 Stockholm, Sweden.
Hideki
H
Matsuda
Pablo R
PR
Brumovsky
Jutta
J
Kopp
Thierry
T
Pedrazzini
Tomas
T
Hökfelt
D000818:Animals; D002319:Cardiovascular System / Q000378:metabolism / Q000648:ultrastructure; D004064:Digestive System / Q000098:blood supply / Q000378:metabolism / Q000648:ultrastructure; D004703:Endocrine System / Q000098:blood supply / Q000378:metabolism / Q000648:ultrastructure; D005260:Female; D005725:Ganglia, Autonomic / Q000098:blood supply / Q000378:metabolism / Q000648:ultrastructure; D008208:Lymphatic System / Q000098:blood supply / Q000378:metabolism / Q000648:ultrastructure; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009131:Muscle, Smooth, Vascular / Q000378:metabolism* / Q000648:ultrastructure; D009474:Neurons / Q000737:chemistry / Q000648:ultrastructure; D009928:Organ Specificity / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017476:Receptors, Neuropeptide Y / Q000172:deficiency / Q000235:genetics / Q000378:metabolism* / Q000648:ultrastructure; D012867:Skin / Q000098:blood supply / Q000378:metabolism / Q000648:ultrastructure; D014132:Trachea / Q000098:blood supply / Q000378:metabolism / Q000648:ultrastructure; D014566:Urogenital System / Q000098:blood supply / Q000378:metabolism / Q000648:ultrastructure
D017476:Receptors, Neuropeptide Y; C097212:neuropeptide Y-Y1 receptor