The Experts below are selected from a list of 162 Experts worldwide ranked by ideXlab platform

Kenneth C Bovee - One of the best experts on this subject based on the ideXlab platform.

  • effects of Bethanechol on canine urinary bladder smooth muscle function
    Research in Veterinary Science, 2001
    Co-Authors: Chollada Buranakarl, Anusak Kijtawornrat, Kris Angkanaporn, Siripen Komolvanich, Kenneth C Bovee
    Abstract:

    We studied whether the effects of Bethanechol are mediated via a muscarinic receptor, the role of extracellular calcium on bladder contraction, and down-regulation of bladder contraction by Bethanechol after activation with potassium chloride (KCl) and acetylcholine (Ach). Smooth muscle strips of normal urinary bladder were studied with standard methods to measure isometric force. Bethanechol caused a dose-dependent increase in bladder contraction. The potency of Bethanechol is higher than Ach, as shown by higher peak active isometric stress (P(max)) and lower half-maximal contraction (ED(50)) (P< 0.01). The contractile responses to Bethanechol were diminished in the presence of atropine, nifedipine and in calcium-free medium as shown by P(max) decreased by 58%, 87% and 65% and ED(50) increased by 314-, 24- and 16-fold, respectively. When bladder strips were stimulated with KCl and Ach, pre-treatment with Bethanechol reduced the responses to KCl by 116-242% (P<0.05), while the contractile responses to Ach were unaltered. Thus, Bethanechol induces bladder contraction via muscarinic receptor activation while both intracellular and extracellular calcium play a crucial role on bladder smooth muscle contraction. The mechanisms of down-regulation by Bethanechol may be related to interference with calcium influx into the smooth muscle cells, rather than the desensitisation of muscarinic receptors or post-receptor steps of signal transduction following Bethanechol binding to the receptor.

  • Effects of Bethanechol on canine urinary bladder smooth muscle function.
    Research in veterinary science, 2001
    Co-Authors: Chollada Buranakarl, Anusak Kijtawornrat, Kris Angkanaporn, Siripen Komolvanich, Kenneth C Bovee
    Abstract:

    We studied whether the effects of Bethanechol are mediated via a muscarinic receptor, the role of extracellular calcium on bladder contraction, and down-regulation of bladder contraction by Bethanechol after activation with potassium chloride (KCl) and acetylcholine (Ach). Smooth muscle strips of normal urinary bladder were studied with standard methods to measure isometric force. Bethanechol caused a dose-dependent increase in bladder contraction. The potency of Bethanechol is higher than Ach, as shown by higher peak active isometric stress (P(max)) and lower half-maximal contraction (ED(50)) (P< 0.01). The contractile responses to Bethanechol were diminished in the presence of atropine, nifedipine and in calcium-free medium as shown by P(max) decreased by 58%, 87% and 65% and ED(50) increased by 314-, 24- and 16-fold, respectively. When bladder strips were stimulated with KCl and Ach, pre-treatment with Bethanechol reduced the responses to KCl by 116-242% (P

Chollada Buranakarl - One of the best experts on this subject based on the ideXlab platform.

  • effects of Bethanechol on canine urinary bladder smooth muscle function
    Research in Veterinary Science, 2001
    Co-Authors: Chollada Buranakarl, Anusak Kijtawornrat, Kris Angkanaporn, Siripen Komolvanich, Kenneth C Bovee
    Abstract:

    We studied whether the effects of Bethanechol are mediated via a muscarinic receptor, the role of extracellular calcium on bladder contraction, and down-regulation of bladder contraction by Bethanechol after activation with potassium chloride (KCl) and acetylcholine (Ach). Smooth muscle strips of normal urinary bladder were studied with standard methods to measure isometric force. Bethanechol caused a dose-dependent increase in bladder contraction. The potency of Bethanechol is higher than Ach, as shown by higher peak active isometric stress (P(max)) and lower half-maximal contraction (ED(50)) (P< 0.01). The contractile responses to Bethanechol were diminished in the presence of atropine, nifedipine and in calcium-free medium as shown by P(max) decreased by 58%, 87% and 65% and ED(50) increased by 314-, 24- and 16-fold, respectively. When bladder strips were stimulated with KCl and Ach, pre-treatment with Bethanechol reduced the responses to KCl by 116-242% (P<0.05), while the contractile responses to Ach were unaltered. Thus, Bethanechol induces bladder contraction via muscarinic receptor activation while both intracellular and extracellular calcium play a crucial role on bladder smooth muscle contraction. The mechanisms of down-regulation by Bethanechol may be related to interference with calcium influx into the smooth muscle cells, rather than the desensitisation of muscarinic receptors or post-receptor steps of signal transduction following Bethanechol binding to the receptor.

  • Effects of Bethanechol on canine urinary bladder smooth muscle function.
    Research in veterinary science, 2001
    Co-Authors: Chollada Buranakarl, Anusak Kijtawornrat, Kris Angkanaporn, Siripen Komolvanich, Kenneth C Bovee
    Abstract:

    We studied whether the effects of Bethanechol are mediated via a muscarinic receptor, the role of extracellular calcium on bladder contraction, and down-regulation of bladder contraction by Bethanechol after activation with potassium chloride (KCl) and acetylcholine (Ach). Smooth muscle strips of normal urinary bladder were studied with standard methods to measure isometric force. Bethanechol caused a dose-dependent increase in bladder contraction. The potency of Bethanechol is higher than Ach, as shown by higher peak active isometric stress (P(max)) and lower half-maximal contraction (ED(50)) (P< 0.01). The contractile responses to Bethanechol were diminished in the presence of atropine, nifedipine and in calcium-free medium as shown by P(max) decreased by 58%, 87% and 65% and ED(50) increased by 314-, 24- and 16-fold, respectively. When bladder strips were stimulated with KCl and Ach, pre-treatment with Bethanechol reduced the responses to KCl by 116-242% (P

Diego Currò - One of the best experts on this subject based on the ideXlab platform.

  • expression and motor functional roles of voltage dependent type 7 k channels in the human taenia coli
    European Journal of Pharmacology, 2013
    Co-Authors: Alice Adduci, Gianluca Rizzo, Claudio Coco, Maurizio Taglialatela, Maria Martire, Vincenzo Arena, Diego Currò
    Abstract:

    Abstract Voltage-dependent type 7 K + (K V 7 or KCNQ) channels modulate the excitability of neurons and muscle cells. The aims of the present study were to investigate the motor effects of K V 7 channel modulators and the expression of K V 7 channels in the human taenia coli . The effects of K V 7 channel modulators on the muscle tone of human taenia coli strips were investigated under nonadrenergic non-nitrergic conditions by organ bath studies. Gene expression and tissue localisation of channels were studied by real-time PCR and immunohistochemistry, respectively. Under basal conditions, the K V 7 channel blocker XE-991 induced concentration-dependent contractions, with mean EC 50 and E max of 18.7 μM and 30.5% respectively of the maximal Bethanechol-induced contraction, respectively. The K V 7 channel activators retigabine and flupirtine concentration-dependently relaxed the taenia coli , with mean EC 50 s of 19.2 μM and 29.9 μM, respectively. Retigabine also relaxed Bethanechol-precontracted strips, with maximal relaxations of 79.2% of the bethanecol-induced precontraction. The motor effects induced by the K V 7 channel modulators were not affected by tetrodotoxin or ω-conotoxin GVIA. XE-991 greatly reduced retigabine- and flupirtine-induced relaxations. Transcripts encoded by all KCNQ genes were detected in the taenia coli , with KCNQ4 showing the highest expression levels. K V 7.4 channels were clearly visualised by immunohistochemistry in colonic epithelium, circular muscle layer and taenia coli . K V 7 channels appear to contribute to the resting muscle tone of the human taenia coli . In addition, K V 7 channel activators significantly relax the taenia coli . Thus, they could be useful therapeutic relaxant agents for colonic motor disorders.

  • Expression and motor functional roles of voltage-dependent type 7 K(+) channels in the human taenia coli.
    European journal of pharmacology, 2013
    Co-Authors: Alice Adduci, Gianluca Rizzo, Claudio Coco, Maurizio Taglialatela, Maria Martire, Vincenzo Arena, Diego Currò
    Abstract:

    Voltage-dependent type 7 K(+) (KV7 or KCNQ) channels modulate the excitability of neurons and muscle cells. The aims of the present study were to investigate the motor effects of KV7 channel modulators and the expression of KV7 channels in the human taenia coli. The effects of KV7 channel modulators on the muscle tone of human taenia coli strips were investigated under nonadrenergic non-nitrergic conditions by organ bath studies. Gene expression and tissue localisation of channels were studied by real-time PCR and immunohistochemistry, respectively. Under basal conditions, the KV7 channel blocker XE-991 induced concentration-dependent contractions, with mean EC50 and Emax of 18.7 μM and 30.5% respectively of the maximal Bethanechol-induced contraction, respectively. The KV7 channel activators retigabine and flupirtine concentration-dependently relaxed the taenia coli, with mean EC50s of 19.2 μM and 29.9 μM, respectively. Retigabine also relaxed Bethanechol-precontracted strips, with maximal relaxations of 79.2% of the bethanecol-induced precontraction. The motor effects induced by the KV7 channel modulators were not affected by tetrodotoxin or ω-conotoxin GVIA. XE-991 greatly reduced retigabine- and flupirtine-induced relaxations. Transcripts encoded by all KCNQ genes were detected in the taenia coli, with KCNQ4 showing the highest expression levels. KV7.4 channels were clearly visualised by immunohistochemistry in colonic epithelium, circular muscle layer and taenia coli. KV7 channels appear to contribute to the resting muscle tone of the human taenia coli. In addition, KV7 channel activators significantly relax the taenia coli. Thus, they could be useful therapeutic relaxant agents for colonic motor disorders.

Anusak Kijtawornrat - One of the best experts on this subject based on the ideXlab platform.

  • effects of Bethanechol on canine urinary bladder smooth muscle function
    Research in Veterinary Science, 2001
    Co-Authors: Chollada Buranakarl, Anusak Kijtawornrat, Kris Angkanaporn, Siripen Komolvanich, Kenneth C Bovee
    Abstract:

    We studied whether the effects of Bethanechol are mediated via a muscarinic receptor, the role of extracellular calcium on bladder contraction, and down-regulation of bladder contraction by Bethanechol after activation with potassium chloride (KCl) and acetylcholine (Ach). Smooth muscle strips of normal urinary bladder were studied with standard methods to measure isometric force. Bethanechol caused a dose-dependent increase in bladder contraction. The potency of Bethanechol is higher than Ach, as shown by higher peak active isometric stress (P(max)) and lower half-maximal contraction (ED(50)) (P< 0.01). The contractile responses to Bethanechol were diminished in the presence of atropine, nifedipine and in calcium-free medium as shown by P(max) decreased by 58%, 87% and 65% and ED(50) increased by 314-, 24- and 16-fold, respectively. When bladder strips were stimulated with KCl and Ach, pre-treatment with Bethanechol reduced the responses to KCl by 116-242% (P<0.05), while the contractile responses to Ach were unaltered. Thus, Bethanechol induces bladder contraction via muscarinic receptor activation while both intracellular and extracellular calcium play a crucial role on bladder smooth muscle contraction. The mechanisms of down-regulation by Bethanechol may be related to interference with calcium influx into the smooth muscle cells, rather than the desensitisation of muscarinic receptors or post-receptor steps of signal transduction following Bethanechol binding to the receptor.

  • Effects of Bethanechol on canine urinary bladder smooth muscle function.
    Research in veterinary science, 2001
    Co-Authors: Chollada Buranakarl, Anusak Kijtawornrat, Kris Angkanaporn, Siripen Komolvanich, Kenneth C Bovee
    Abstract:

    We studied whether the effects of Bethanechol are mediated via a muscarinic receptor, the role of extracellular calcium on bladder contraction, and down-regulation of bladder contraction by Bethanechol after activation with potassium chloride (KCl) and acetylcholine (Ach). Smooth muscle strips of normal urinary bladder were studied with standard methods to measure isometric force. Bethanechol caused a dose-dependent increase in bladder contraction. The potency of Bethanechol is higher than Ach, as shown by higher peak active isometric stress (P(max)) and lower half-maximal contraction (ED(50)) (P< 0.01). The contractile responses to Bethanechol were diminished in the presence of atropine, nifedipine and in calcium-free medium as shown by P(max) decreased by 58%, 87% and 65% and ED(50) increased by 314-, 24- and 16-fold, respectively. When bladder strips were stimulated with KCl and Ach, pre-treatment with Bethanechol reduced the responses to KCl by 116-242% (P

Kris Angkanaporn - One of the best experts on this subject based on the ideXlab platform.

  • effects of Bethanechol on canine urinary bladder smooth muscle function
    Research in Veterinary Science, 2001
    Co-Authors: Chollada Buranakarl, Anusak Kijtawornrat, Kris Angkanaporn, Siripen Komolvanich, Kenneth C Bovee
    Abstract:

    We studied whether the effects of Bethanechol are mediated via a muscarinic receptor, the role of extracellular calcium on bladder contraction, and down-regulation of bladder contraction by Bethanechol after activation with potassium chloride (KCl) and acetylcholine (Ach). Smooth muscle strips of normal urinary bladder were studied with standard methods to measure isometric force. Bethanechol caused a dose-dependent increase in bladder contraction. The potency of Bethanechol is higher than Ach, as shown by higher peak active isometric stress (P(max)) and lower half-maximal contraction (ED(50)) (P< 0.01). The contractile responses to Bethanechol were diminished in the presence of atropine, nifedipine and in calcium-free medium as shown by P(max) decreased by 58%, 87% and 65% and ED(50) increased by 314-, 24- and 16-fold, respectively. When bladder strips were stimulated with KCl and Ach, pre-treatment with Bethanechol reduced the responses to KCl by 116-242% (P<0.05), while the contractile responses to Ach were unaltered. Thus, Bethanechol induces bladder contraction via muscarinic receptor activation while both intracellular and extracellular calcium play a crucial role on bladder smooth muscle contraction. The mechanisms of down-regulation by Bethanechol may be related to interference with calcium influx into the smooth muscle cells, rather than the desensitisation of muscarinic receptors or post-receptor steps of signal transduction following Bethanechol binding to the receptor.

  • Effects of Bethanechol on canine urinary bladder smooth muscle function.
    Research in veterinary science, 2001
    Co-Authors: Chollada Buranakarl, Anusak Kijtawornrat, Kris Angkanaporn, Siripen Komolvanich, Kenneth C Bovee
    Abstract:

    We studied whether the effects of Bethanechol are mediated via a muscarinic receptor, the role of extracellular calcium on bladder contraction, and down-regulation of bladder contraction by Bethanechol after activation with potassium chloride (KCl) and acetylcholine (Ach). Smooth muscle strips of normal urinary bladder were studied with standard methods to measure isometric force. Bethanechol caused a dose-dependent increase in bladder contraction. The potency of Bethanechol is higher than Ach, as shown by higher peak active isometric stress (P(max)) and lower half-maximal contraction (ED(50)) (P< 0.01). The contractile responses to Bethanechol were diminished in the presence of atropine, nifedipine and in calcium-free medium as shown by P(max) decreased by 58%, 87% and 65% and ED(50) increased by 314-, 24- and 16-fold, respectively. When bladder strips were stimulated with KCl and Ach, pre-treatment with Bethanechol reduced the responses to KCl by 116-242% (P