caa a22 4500 469077964 CHVBK 20180323132940.0 cr unu---uuuuu 170328e19921201xx s 000 0 eng 10.1007/BF00168731 doi (NATIONALLICENCE)springer-10.1007/BF00168731 Chloride channels of skeletal muscle from developing, adult and aged rats are differently affected by enantiomers of 2-(p-chlorophenoxy) propionic acid [Elektronische Daten] [A. De Luca, V. Tortorella, D. Conte Camerino] Summary: Enantiomers of 2-(p-chlorophenoxy) propionic acid, compounds acting specifically on chloride channels of adult rat skeletal muscles, have been tested on extensor digitorum longus (EDL) muscle of developing and aged rats, in an attempt to characterize the chloride channels responsible for the low chloride conductance (GC1) found in the above physiological situations. The S-(−) enantiomer, which produces a concentration-dependent inhibition of GC1 in the adult EDL, is less effective in inhibiting GC1 of EDL of either 2-3 weeks or 29 months old rats, particularly at low concentrations. The R-(+) isomer, which in the adult enhances GC1 at low concentrations and blocks it at concentrations higher than 10 μM, lacks inhibitory action, enhancing GC1 in both developing and aged EDL. At 30-40 days of age both the enantiomers produce almost the same effects exerted in adulthood. From these data we hypothesize that the low GC1 found in EDL of developing and aged rats might be due not only to a lower number of conductive channels but also to the presence of a mixed population of isoforms of chloride channels having different pharmacological properties. Springer-Verlag, 1992 Skeletal muscle nationallicence Chloride channel nationallicence Postnatal development nationallicence Aging nationallicence Pharmacological characterization nationallicence De Luca A. Dipartimento Farmacobiologico, Unità di Farmacologia, Italy aut Tortorella V. Dipartimento Farmacobiologico, Unità di Farmacologia, Italy aut Conte Camerino D. Dipartimento Farmacochimico, Facoltà di Farmacia, Università di Bari, Trav. 200 Re David, 4, I-70125, Bari, Italy aut Naunyn-Schmiedeberg's Archives of Pharmacology Springer-Verlag 346/6(1992-12-01), 601-606 0028-1298 346:6<601 1992 346 210 https://doi.org/10.1007/BF00168731 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00168731 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- De Luca A. Dipartimento Farmacobiologico, Unità di Farmacologia, Italy aut NATIONALLICENCE 700 1- Tortorella V. Dipartimento Farmacobiologico, Unità di Farmacologia, Italy aut NATIONALLICENCE 700 1- Conte Camerino D. Dipartimento Farmacochimico, Facoltà di Farmacia, Università di Bari, Trav. 200 Re David, 4, I-70125, Bari, Italy aut NATIONALLICENCE 773 0- Naunyn-Schmiedeberg's Archives of Pharmacology Springer-Verlag 346/6(1992-12-01), 601-606 0028-1298 346:6<601 1992 346 210 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer