Jonathan A. Ferrar

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Somatostatin-14 (SS-14) and somatostatin-28 (SS-28) produce concentration dependent reductions in short-circuit current in rat colonic mucosa. EC50 values of 15.0 and 13.3 nM were obtained for SS-14 and SS-28 respectively while the N-terminal fragments of SS-28, namely somatostatin-(1-12) (SS1-12) and somatostatin-(1-14) (SS1-14) were inactive.(More)
Preparations of rat descending colon mucosa have been used to record changes in short circuit current (SCC) under voltage clamp conditions. When added to the basolateral compartment capsaicin (8-methyl-N-vanillyl-6-nonenamide, 0.1-3 μM) caused an initial transient increase in SCC, followed by a more prolonged reduction in SCC, that lasted for 20–30 min.(More)
Both alpha- and beta-calcitonin gene-related peptide (CGRP) exhibit concentration-dependent dual actions upon rat colonic epithelia. At low concentrations (i.e. 0.03-10 nM) both CGRPs produce antisecretory effects that are abolished by pretreating tissues with tetrodotoxin (TTX). At higher concentrations (30-200 nM) secretory responses predominate and these(More)
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