Premium
Role of Neuropeptide Y in the Regulation of Tyrosine Hydroxylase Messenger Ribonucleic Acid Levels in the Male Rat Arcuate Nucleus as Evaluated by in situ Hybridization
Author(s) -
Hong Min,
Li Songyun,
Pelletier Georges
Publication year - 1995
Publication title -
journal of neuroendocrinology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.062
H-Index - 116
eISSN - 1365-2826
pISSN - 0953-8194
DOI - 10.1111/j.1365-2826.1995.tb00663.x
Subject(s) - medicine , endocrinology , neuropeptide y receptor , arcuate nucleus , tyrosine hydroxylase , in situ hybridization , agonist , biology , hypothalamus , dopaminergic , receptor , dopamine , neuropeptide , chemistry , gene expression , biochemistry , gene
Neuroanatomical data have clearly demonstrated the existence of synaptic contacts between neuropeptide Y (NPY) endings and tuberoinfundibular dopaminergic (TIDA) neurons in the rat arcuate nucleus. In order to determine the influence of NPY in the biosynthesis of dopamine, we have studied the effects of NPY and some NPY analogs on tyrosine hydroxylase (TH) gene expression in TlDA neurons in the male rat. The following peptides: NPY, PYY, [Leu 31 , Pro 34 ]‐NPY (a Y, receptor agonist) and NPY 13–36 (a Y 2 receptor agonist) were injected into the left lateral ventricle of adult male rats. All the animals were perfused with 4% paraformaldehyde 4 h after injection. Cryostat sections through the arcuate nucleus were processed for quantitative in situ hybridization. The intracerebroventricular injection of NPY, PYY and [Leu 31 , Pro 34 ]‐NPY induced an increased of 43, 33 and 42%, respectively, in the number of grains overlying TH neurons. On the other hand, the Y 2 receptor agonist NPY 13–36 did not influence mRNA levels. These data then strongly suggest that NPY positively regulates the genetic expression of TH in rat TlDA neurons via the Y, NPY receptor subtype.