[Effects of motilin agonists on intracellular calcium mobilization in cultured rat myenteric neurons].
OBJECTIVE
To investigate the effects of motilin agonists on intracellular Ca(2+) mobilization in primary cultured rat myenteric neurons.


METHODS
Motilin-induced and erythromycin-induced intracellular Ca(2+) signaling was studied in primary cultures of rat myenteric neurons using the radiometric Ca(2+) indicator Furo3/AM with a laser confocal microscope.


RESULTS
In Hank's solution, 10(-8), 10(-7), and 10(-6) mol/L motilin could elevate intracellular Ca(2+) concentration ([Ca(2+)]i) to the peak levels of 10.6-/+2.1, 15.9-/+1.2, and 30.6-/+3.7 respectively with their relative percentage change in fluorescent intensity of (40.1-/+6.3)%, (63.0-/+11.2)%, and (100.8-/+18.4)% respectively, indicating the dose-dependent effect of motilin on [Ca(2+)]i. In Hank's solution, 10 microg/ml erythromycin could induce the elevation of [Ca(2+)]i to the average peak of 23.2-/+5.6 with the relative percentage change in fluorescent intensity of (82.8-/+13.0)%. When pretreated with the antibody against motilin receptor in Hank's solution, the effect of 10 microg/ml erythromycin was almost inhibited completely.


CONCLUSIONS
Motilin can increase [Ca(2+)]i, and erythromycin also has this effect by binding to motilin receptor.
Yang
Xia
X
Department of Gastroenterology, Second Hospital of Xi'an Jiaotong University, Xi'an 710004, China. muyirenjia@sohu.com
Dong
Lei
L
Yang
Xi-en
XE
D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism*; D020013:Calcium Signaling / Q000187:drug effects; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004917:Erythromycin / Q000494:pharmacology*; D018613:Microscopy, Confocal; D009037:Motilin / Q000494:pharmacology*; D009197:Myenteric Plexus / Q000166:cytology / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011964:Receptors, Gastrointestinal Hormone / Q000819:agonists*; D018013:Receptors, Neuropeptide / Q000819:agonists*
D011964:Receptors, Gastrointestinal Hormone; D018013:Receptors, Neuropeptide; C050802:motilin receptor; D009037:Motilin; D004917:Erythromycin; D002118:Calcium