Journal article

Publication year: 2004

Pages: 605-612

Journal: Pflügers Archiv European Journal of Physiology

Volume number: 448

Issue number: 6

ISSN: 0031-6768

eISSN: 1432-2013

DOI Link: https://doi.org/10.1007/s00424-004-1299-9

Publisher: Springer

Abstract: 
Dopamine (5.10(-6)-5.10(-4) M) induced a concentration-dependent decrease in short-circuit current (I-sc) across the rat distal colon. This response was preceded by a transient and inconsistent increase in I-sc. The alpha-adrenoceptor blocker phentolamine and the inhibitors of dopamine-2-like (D-2-like) receptors L-741,626 and L-745,870 inhibited the dopamine response, suggesting a contribution of adrenergic and dopaminergic receptors. The decrease in,,, evoked by dopamine was inhibited by bumetanide, an inhibitor of the basolateral Na+-K+-2 Cl- cotransporter responsible for the uptake of K+, and by quinine, a blocker of apical K+ channels, indicating that stimulation of K+ secretion contributes to the measured change in I-sc. In patch-clamp experiments dopamine hyperpolarized the membrane and increased cellular K+ current. This response was not concomitant with a change in the intracellular [Ca2+] as demonstrated in parallel fura-2 experiments. These results demonstrate that dopamine, like other catecholamines, stimulates colonic K+ secretion.

Harvard Citation style: Al-Jahmany, A., Schultheiss, G. and Diener, M. (2004) Effects of dopamine on ion transport across the rat distal colon, Pflügers Archiv European Journal of Physiology, 448(6), pp. 605-612. https://doi.org/10.1007/s00424-004-1299-9

APA Citation style: Al-Jahmany, A., Schultheiss, G., & Diener, M. (2004). Effects of dopamine on ion transport across the rat distal colon. Pflügers Archiv European Journal of Physiology. 448(6), 605-612. https://doi.org/10.1007/s00424-004-1299-9