Abstract
Both salmon calcitonin (SCT) and substance P decreased ileal Na absorption, changed Cl transport from net absorption to net secretion and elevated the short circuit current when added in vitro at concentrations of 10 microng per ml to solutions bathing the serosal surface of rat ileum which had been stripped of its serosal muscle coat. The effects of substance P were of greater magnitude but shorter duration than SCT. Both peptides also increased the bidirectional fluxes of Ca but did not alter net Ca movement. The changes in Na and Cl fluxes and short circuit current are identifical to those which occur when cellular levels of cyclic AMP increased. However, incubation of ileal mucosa with SCT or substance P did not cause a detectable change in cellular levels of cyclic AMP or cyclic GMP. Both the mechanism of action and the possible physiological functions of SCT and substance P in the regulation of electrolyte transport require further investigation. The results with SCT appear to confirm prior suggestions that calcitonin may act directly to produce secretory diarrhea under pathophysiological conditions.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.