Poly(lactic acid) microspheres for the sustained release of a selective A1 receptor agonist
| Autor: | Maria Angela Vandelli, Angelo Scatturin, Carla Biondi, Flavio Forni, Alessandro Dalpiaz, Barbara Pavan |
|---|---|
| Rok vydání: | 2001 |
| Předmět: |
Adenosine monophosphate
Adenosine Polymers Polyesters PLA microscpheres A1 receptor agonist Pharmaceutical Science Adenosine A1 receptor chemistry.chemical_compound Drug Stability Cyclic AMP Purinergic P1 Receptor Agonists medicine Humans heterocyclic compounds Lactic Acid Whole blood Chromatography Biological activity Microspheres Lactic acid chemistry Biochemistry Delayed-Action Preparations Xanthines cardiovascular system Liberation Drug carrier medicine.drug |
| Zdroj: | Journal of Controlled Release. 73:303-313 |
| ISSN: | 0168-3659 |
| Popis: | A study concerning the feasibility of microsphere use as sustained delivery systems for N 6 -cyclopentyladenosine (CPA) administration has been performed. The release of this drug and the related stability effects in human whole blood have been tested. Moreover, the impact of the delivery system on CPA interaction toward human adenosine A 1 receptor and the related cellular responses has been analyzed. The microspheres were prepared by an emulsion–solvent evaporation method using poly(lactic acid). Free and encapsulated CPA was incubated in fresh blood and the drug stability was analyzed with HPLC. The affinity of CPA to human A 1 receptor expressed by CHO cells was obtained by binding experiments. Activity was evaluated by measurements of the inhibition of forskolin-stimulated 3′,5′-cyclic adenosine monophosphate (c-AMP) performing competitive binding assays. Encapsulated CPA was released within 72 h and its degradation in blood was negligible. Affinity and activity values of CPA obtained in the absence and in the presence of unloaded microspheres were the same. CPA encapsulation in microspheres allows its sustained release and its stabilization in human whole blood to be obtained. The presence of this release system does not interfere with the CPA activity at its action site. |
| Databáze: | OpenAIRE |
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