Smooth muscle cells (SMC) from the circular muscle layer of rabbit colon, taken from the proximal and distal regions that are known to have different physiological and motor activities, were used to highlight distinct regional intrinsic myogenic properties and to investigate the correlations between receptor and signalling transduction pathways. Contractile agonists were shown to be more potent on proximal than on distal SMC in inducing contraction and intracellular Ca2+ increase. Concentration-response curves of agonists-induced Ca2+ increase were constantly shifted to the right, though remaining parallel, with respect to contraction curves, independently of the region analysed. Using agents activating different steps of cAMP-or cGMP-mediated intracellular cascades, main regional differences were revealed as far as relaxation was concerned. Relaxation of proximal SMC was found to be essentially cGMP mediated, while that of distal SMC was cAMP mediated. In conclusion, the motor patterns of the two regions appear to be influenced by distinct regional biochemical characteristics that are intrinsic to colonic SMC. (C) 2000 Elsevier Science Inc. All rights reserved.
Regional differences in signalling transduction pathways among smooth muscle cells from rabbit colon / V., Carnicelli; A., Di Giulio; G., Romano; A., Bozzi; A., Oratore; DELLE FAVE, Gianfranco; Strom, Roberto; Severi, Carola. - In: CELLULAR SIGNALLING. - ISSN 0898-6568. - STAMPA. - 12:9-10(2000), pp. 683-689. [10.1016/s0898-6568(00)00114-5]
Regional differences in signalling transduction pathways among smooth muscle cells from rabbit colon
DELLE FAVE, Gianfranco;STROM, Roberto;SEVERI, Carola
2000
Abstract
Smooth muscle cells (SMC) from the circular muscle layer of rabbit colon, taken from the proximal and distal regions that are known to have different physiological and motor activities, were used to highlight distinct regional intrinsic myogenic properties and to investigate the correlations between receptor and signalling transduction pathways. Contractile agonists were shown to be more potent on proximal than on distal SMC in inducing contraction and intracellular Ca2+ increase. Concentration-response curves of agonists-induced Ca2+ increase were constantly shifted to the right, though remaining parallel, with respect to contraction curves, independently of the region analysed. Using agents activating different steps of cAMP-or cGMP-mediated intracellular cascades, main regional differences were revealed as far as relaxation was concerned. Relaxation of proximal SMC was found to be essentially cGMP mediated, while that of distal SMC was cAMP mediated. In conclusion, the motor patterns of the two regions appear to be influenced by distinct regional biochemical characteristics that are intrinsic to colonic SMC. (C) 2000 Elsevier Science Inc. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
