Can [125I]-iodocyanopindolol label ß3-adrenoceptors in rat urinary bladder?
β3-Adrenoceptors have been demonstrated to mediate urinary bladder smooth muscle relaxation but proof of their expression at the protein level has been missing because of lack of suitable antibodies or radioligands. As among various available radioligands [125I]-iodocyanopindolol ([125I]-ICYP) exhib...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2010-10-01
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| Series: | Frontiers in Pharmacology |
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| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fphar.2010.00128/full |
| _version_ | 1828527967705235456 |
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| author | Tim eSchneider Martin Christian Michel |
| author_facet | Tim eSchneider Martin Christian Michel |
| author_sort | Tim eSchneider |
| collection | DOAJ |
| description | β3-Adrenoceptors have been demonstrated to mediate urinary bladder smooth muscle relaxation but proof of their expression at the protein level has been missing because of lack of suitable antibodies or radioligands. As among various available radioligands [125I]-iodocyanopindolol ([125I]-ICYP) exhibited the smallest problems in labelling cloned human β3-adrenoceptors in previous studies, we have explored its suitability to label β3-adrenoceptors in rat urinary bladder in saturation and competition radioligand binding experiments. Rat lung was used as an internal control and exhibited all characteristics expected from this tissue with regard to β1/β2-adrenoceptor labelling. Saturation and competition binding studies with [125I]-ICYP in rat bladder yielded saturable binding sites with an affinity compatible with β3-adrenoceptors. In competition experiments various agonists and antagonists largely exhibited a profile compatible with a population consisting largely of β3-adrenoceptors. However, the binding competition properties of ICI 118,551 and SR 59,230A were not easily explained by the idea of labelling a homogeneous β3-adrenoceptor population but interpretation of the data was limited by a high degree of non-specific binding in [125I]-ICYP concentrations required to label the receptors. We conclude that [125I]-ICYP can be used to label tissue β3-adrenoceptors but results obtained with this ligand have to be interpreted with caution. |
| first_indexed | 2024-12-11T21:45:36Z |
| format | Article |
| id | doaj.art-f3347ef733234fddb1d8c3b22338c50d |
| institution | Directory Open Access Journal |
| issn | 1663-9812 |
| language | English |
| last_indexed | 2024-12-11T21:45:36Z |
| publishDate | 2010-10-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Pharmacology |
| spelling | doaj.art-f3347ef733234fddb1d8c3b22338c50d2022-12-22T00:49:38ZengFrontiers Media S.A.Frontiers in Pharmacology1663-98122010-10-01110.3389/fphar.2010.001287200Can [125I]-iodocyanopindolol label ß3-adrenoceptors in rat urinary bladder?Tim eSchneider0Martin Christian Michel1University of EssenAcademic Medical Centerβ3-Adrenoceptors have been demonstrated to mediate urinary bladder smooth muscle relaxation but proof of their expression at the protein level has been missing because of lack of suitable antibodies or radioligands. As among various available radioligands [125I]-iodocyanopindolol ([125I]-ICYP) exhibited the smallest problems in labelling cloned human β3-adrenoceptors in previous studies, we have explored its suitability to label β3-adrenoceptors in rat urinary bladder in saturation and competition radioligand binding experiments. Rat lung was used as an internal control and exhibited all characteristics expected from this tissue with regard to β1/β2-adrenoceptor labelling. Saturation and competition binding studies with [125I]-ICYP in rat bladder yielded saturable binding sites with an affinity compatible with β3-adrenoceptors. In competition experiments various agonists and antagonists largely exhibited a profile compatible with a population consisting largely of β3-adrenoceptors. However, the binding competition properties of ICI 118,551 and SR 59,230A were not easily explained by the idea of labelling a homogeneous β3-adrenoceptor population but interpretation of the data was limited by a high degree of non-specific binding in [125I]-ICYP concentrations required to label the receptors. We conclude that [125I]-ICYP can be used to label tissue β3-adrenoceptors but results obtained with this ligand have to be interpreted with caution.http://journal.frontiersin.org/Journal/10.3389/fphar.2010.00128/fullLungUrinary Bladderrat[125I]-iodocyanopindololβ3-adrenoceptor |
| spellingShingle | Tim eSchneider Martin Christian Michel Can [125I]-iodocyanopindolol label ß3-adrenoceptors in rat urinary bladder? Frontiers in Pharmacology Lung Urinary Bladder rat [125I]-iodocyanopindolol β3-adrenoceptor |
| title | Can [125I]-iodocyanopindolol label ß3-adrenoceptors in rat urinary bladder? |
| title_full | Can [125I]-iodocyanopindolol label ß3-adrenoceptors in rat urinary bladder? |
| title_fullStr | Can [125I]-iodocyanopindolol label ß3-adrenoceptors in rat urinary bladder? |
| title_full_unstemmed | Can [125I]-iodocyanopindolol label ß3-adrenoceptors in rat urinary bladder? |
| title_short | Can [125I]-iodocyanopindolol label ß3-adrenoceptors in rat urinary bladder? |
| title_sort | can 125i iodocyanopindolol label ss3 adrenoceptors in rat urinary bladder |
| topic | Lung Urinary Bladder rat [125I]-iodocyanopindolol β3-adrenoceptor |
| url | http://journal.frontiersin.org/Journal/10.3389/fphar.2010.00128/full |
| work_keys_str_mv | AT timeschneider can125iiodocyanopindolollabelß3adrenoceptorsinraturinarybladder AT martinchristianmichel can125iiodocyanopindolollabelß3adrenoceptorsinraturinarybladder |