Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043167 (pertussis)
 19,595 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

2-Chloroadenosine reduced the contractile tension of guinea-pig atria directly, and inhibited the increase in tension produced by beta-adrenergic stimulation of guinea-pig papillary muscle. Both effects were reduced by 8-phenyltheophylline, a competitive antagonist at extracellular P1-purinoceptors. Treatment of guinea-pigs with pertussis toxin reduced the sensitivity of both atria and ventricles to 2-chloroadenosine. Atria were significantly affected after treatment with 125 micrograms/kg toxin, but not 100 micrograms/kg. 60 micrograms/kg toxin had no effect on the sensitivity of the ventricles, but 100 and 125 micrograms/kg significantly decreased the antiadrenergic effect of 2-chloroadenosine. We conclude that both the direct and antiadrenergic effects are mediated by an inhibitory guanine nucleotide binding protein.
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PMID:Pertussis toxin reduces the antiadrenergic effect of 2-chloroadenosine on papillary muscle and the direct negative inotropic effect of 2-chloroadenosine on atrium. 366 35

The effect of purinergic compounds on [Ca2+]i and membrane currents of cell lines derived from the airway epithelium of normal and cystic fibrosis individuals has been investigated. 2-Chloroadenosine (2-CADO), as well as other agonists of the A1 adenosine receptors, causes a transient elevation of cytosolic [Ca2+] that is antagonized by the A1 adenosine receptor antagonist 8-cyclopentyl-1,3 dipropylxanthine (DPCPX). ATP is also effective, but at a lower extent. The [Ca2+]i increase induced by 2-CADO and ATP is abolished by preincubation with phorbol 12-myristate 13-acetate and the Ca(2+)-ATPase inhibitor thapsigargin. This latter result suggests that purinergic agonists mobilize Ca2+ from inositol 1,4,5-trisphosphate-sensitive stores. Pertussis toxin completely inhibits the effect of 2-CADO, whereas only it partially affects that of ATP, suggesting the involvement of different types of G proteins. Perforated patch clamp experiments carried out in both current clamp and voltage clamp modes show that 2-CADO and ATP activate K(+)- and Cl(-)-selective membrane currents, with a mechanism inhibited by preincubation with DPCPX and thapsigargin. These data indicate that activation of adenosine A1 receptor, in a similar way to ATP receptor, causes [Ca2+]i increase and ion channels activation through a transduction mechanism that is not impaired in cystic fibrosis airway epithelial cells.
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PMID:ATP and A1 adenosine receptor agonists mobilize intracellular calcium and activate K+ and Cl- currents in normal and cystic fibrosis airway epithelial cells. 822 38

The ability of adenosine (ADO) to inhibit proliferation and protein synthesis (in particular, collagen synthesis) in cardiac fibroblasts (CF) may ameliorate adverse cardiac remodeling and fibrosis seen in heart failure patients. However, little is known about the signaling pathways that ADO may modulate in CF to alter cell phenotype. Accordingly, this study was designed to identify ADO receptors (AR) and the signaling pathways linked to them in primary cultures of adult rat CF. Quantitative RT-PCR data indicate that the mRNAs for all four known ARs (A(1)R, A(2a)R, A(2b)R, and A(3)R) are present in rat CF, with a greater prevalence of A(2) receptor subtypes. No coupling of AR to the G(q)-phospholipase C signaling pathway or to mobilization of calcium is measurable. Studies using subtype specific agents imply that the A(2a)R and A(2b)R couple to G(s)-adenylyl cyclase and A(1)R couple weakly to G(i)-adenylyl cyclase. 2-Chloroadenosine, 5'-N-ethylcarboxamidoadensoine, and other agents that elevate cellular cAMP stimulate extracellular signal-regulated kinase 1/2 activity in a pertussis toxin-insensitive manner. We conclude that a combination of cAMP-dependent signals generated via A(2a) and A(2b) receptors likely mediate ADO signaling in adult rat CF.
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PMID:Adenosine receptors and second messenger signaling pathways in rat cardiac fibroblasts. 1924 82