Publications by authors named "Charles A Rizzo"

Background: Functional alpha1- and alpha2-adrenoreceptor subtype pharmacology was characterized in an in vitro human nasal mucosa contractile bioassay.

Methods: Nasal mucosa was obtained from 49 donor patients and mucosal strips were placed in chambers filled with Krebs-Ringer solution and attached to isometric force transducers.

Results: Nonselective a-adrenoreceptor agonists epinephrine, norepinephrine, and oxymetazoline produced concentration-dependent contractions of isolated human nasal mucosa (pD2 = 5.

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Hypotonic stimulation induces airway constriction in normal and asthmatic airways. However, the osmolarity sensor in the airway has not been characterized. TRPV4 (also known as VR-OAC, VRL-2, TRP12, OTRPC4), an osmotic-sensitive cation channel in the transient receptor potential (TRP) channel family, was recently cloned.

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The mammalian tachykinin (TK) peptides and their three neurokinin (NK) receptors represent an effector system with wide-ranging actions on neuronal, airway smooth muscle, mucosal, endothelial, immune, inflammatory and remodeling cell function. Recent clinical and preclinical data suggests pathophysiological relevance for TKs in various diseases including asthma, emesis and depression. The promiscuous TK-NK receptor interactions and incompletely overlapping functions mediated by each NK receptor may indicate added therapeutic benefit of using multiple NK receptor blockade.

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Optical difference spectroscopy was used to identify and quantify human adrenal microsomal and mitochondrial cytochrome P450 enzyme interactions with the histamine H(3) receptor antagonists thioperamide, clobenpropit and ciproxifan. Addition of these structurally diverse imidazole H(3) receptor antagonists to cytochrome-P450-containing human adrenal microsomal and mitochondrial preparations resulted in concentration-dependent type II optical difference spectra. Respective spectral dissociation constants (K(S)) for the drug interactions with human adrenal microsomal and mitochondrial cytochrome P450 were 1.

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A novel series of dual NK(1)/NK(2) receptor antagonists, based on the 2-oxo-(1,4'-bipiperidine) template, has been prepared. Compound 10R is a potent dual NK(1)/NK(2) antagonist and demonstrates excellent in vivo activity and good oral plasma levels in the dog.

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N-(3,5-Dichloro-1-oxido-4-pyridinyl)-8-methoxy-2-(trifluoromethyl)-5-quinoline carboxamide (SCH 351591) has been identified as a potent (IC(50) = 58 nM) and highly selective type 4 phosphodiesterase (PDE4) inhibitor with oral bioactivity in several animal models of lung inflammation. N-(3,5-Dichloro-4-pyridinyl)-8-methoxy-2-(trifluoromethyl)-5-quinoline carboxamide (SCH 365351), the only significant in vivo metabolite, is also a potent and highly selective PDE4 inhibitor (IC(50) = 20 nM). Both SCH 351591 and SCH 365351 inhibited cytokine production in human blood mononuclear cell preparations.

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Background: The role of IL-5-induced eosinophilia in airway hyperresponsiveness has been questioned. In addition, eosinophil-independent IL-5-induced airway hyperresponsiveness has been demonstrated in animals.

Objective: In this study, IL-5 was investigated for direct effects on human bronchial responsiveness.

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Nociceptin/orphanin FQ (N/OFQ), an endogenous opioid-like orphan receptor (NOP receptor, previously termed ORL1 receptor) agonist, has been found to inhibit capsaicin-induced bronchoconstriction in isolated guinea-pig lungs and in vivo. The underlying mechanisms are not clear. In the present studies, we tested the effect of N/OFQ on VR1 channel function in isolated guinea-pig nodose ganglia cells.

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