TY - JOUR
T1 - VIP-induced alterations in cAMP and inositol phosphates in the lower esophageal sphincter
AU - Szewczak, S. M.
AU - Behar, J.
AU - Billett, G.
AU - Hillemeier, C.
AU - Rhim, B. Y.
AU - Biancani, P.
PY - 1990
Y1 - 1990
N2 - Adenosine 3',5'-cyclic monophosphate (cAMP), guanosine 3',5'-cyclic monophospahte (cGMP), and inositol phosphate (IP) levels were measured in thin tissue samples from the circular smooth muscle of the cat lower esophageal sphincter (LES) at 37°C during vasoactive intestinal peptide (VIP)-induced relaxation. On exposure of in vitro LES circular muscle strips to 10-6 M VIP at the same temperature, relaxation of spontaneous resting tone begins within 3-6 s, is half maximal at 30 s, and maximal at 1 min. VIP-induced changes in cAMP, cGMP, and IP metabolite levels were measured at 5 and 30 s after the addition of 10-6 M VIP. At 5 s cAMP levels increased significantly with respect to time-matched unstimulated controls, whereas inositol 1,4,5-trisphosphate (1,4,5-IP3) decreased and these changes remained constant at 30 s. cGMP levels were unchanged at either 5 or 30 s after exposure to 10-6 M VIP. These data suggest that VIP-induced relaxation is temporally linked to decreased 1,4,5-IP3 as well as increased cAMP levels.
AB - Adenosine 3',5'-cyclic monophosphate (cAMP), guanosine 3',5'-cyclic monophospahte (cGMP), and inositol phosphate (IP) levels were measured in thin tissue samples from the circular smooth muscle of the cat lower esophageal sphincter (LES) at 37°C during vasoactive intestinal peptide (VIP)-induced relaxation. On exposure of in vitro LES circular muscle strips to 10-6 M VIP at the same temperature, relaxation of spontaneous resting tone begins within 3-6 s, is half maximal at 30 s, and maximal at 1 min. VIP-induced changes in cAMP, cGMP, and IP metabolite levels were measured at 5 and 30 s after the addition of 10-6 M VIP. At 5 s cAMP levels increased significantly with respect to time-matched unstimulated controls, whereas inositol 1,4,5-trisphosphate (1,4,5-IP3) decreased and these changes remained constant at 30 s. cGMP levels were unchanged at either 5 or 30 s after exposure to 10-6 M VIP. These data suggest that VIP-induced relaxation is temporally linked to decreased 1,4,5-IP3 as well as increased cAMP levels.
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U2 - 10.1152/ajpgi.1990.259.2.g239
DO - 10.1152/ajpgi.1990.259.2.g239
M3 - Article
C2 - 2166440
AN - SCOPUS:0025122931
SN - 0193-1849
VL - 259
SP - G239-G244
JO - American Journal of Physiology
JF - American Journal of Physiology
IS - 2 22-2
ER -