Neuropeptide Y Y1 receptor mechanisms in sympathetic vascular control.

摘要: The Y1 receptor is the predominant vascular NPY subtype in pig hind limb and kidney. Thus, responses to exogenous endogenous were almost or totally abolished presence of antagonist BIBP 3226. Furthermore, dose-dependent renal vasoconstriction was evoked by a Y1, but not Y2, agonist, this could be strongly reduced SR 120107A. Moreover, expression receptors kidney artery indicated RT-PCR mRNA for detected small intrarenal arteries using situ hybridization. In contrast, spleen contains both Y2 receptors. vivo, agonists splenic vasoconstriction, which influenced, respectively, Accordingly, spleen. Presence also demonstrated autoradiographic membrane binding studies. dog RT-PCR, binding, latter indicating existence addition, vivo RT-PCR. 2. Selectivity 120107A demonstrated, as agonist displaced with great affinity, contrast 3226 potently tritiated from membranes. exerted potent antagonistic effects on contractions guinea-pig caval vein vitro. inhibition competitive slope Schild plot significantly different unity. appeared effective antagonize NPY-evoked vessel neither affected NA. antagonized mediated vivo. vasoconstrictor via other receptors, including affected. shown have long duration action equally antagonism endogenous, neurogenically released, elimination plasma fit two-compartment model, resulting half-life 2 20 min alpha- beta-phase, respectively. It concluded that continuous infusions are preferable infections during experiments, since non-specific can avoided, under better control. 3. This study presents final pharmacological evidence involvement sympathetic vasoconstriction. released acting mediates long-lasting vena cava phase contraction high frequency stimulation perivascular nerves vessel, leaving merely an initial adrenergic peak contraction. Enantioselective neurogenically-evoked 3435, S-enantiomer virtually devoid largely without effect. Evidence presented nonadrenergic nasal mucosa upon reserpine-treated (ABSTRACT TRUNCATED)