Canine enteric submucosal cultures: transmitter release from neurotensin-immunoreactive neurons.
A culture system of dispersed submucosal neurons from canine ileum has been developed. The neuronal nature of over 80% of the cells in culture was confirmed by positive staining with a neurofilament antibody. In this culture system, neurotensin-immunoreactive neurons constituted greater than 50% of the total cell population. Neurotensin immunoreactivity in these cells was chromatographically characterized as a single molecular form coeluting with synthetic neurotensin (1-13). We have assessed the release of immunoreactive neurotensin by stimulatory and inhibitory transmitters, and by post-receptor activators of cell function. Forskolin (10 microM), the calcium ionophore A23187 (100 nM), and the active phorbol ester beta-12 myristrate 13-acetate (10 nM), each significantly increased neurotensin release compared with basal peptide secretion. The concomitant application of ionophore and phorbol ester resulted in a marked increase in neurotensin release and this stimulatory response was inhibited over 70% by somatostatin (100 nM). Substance P (0.1-100 nM) caused a dose-dependent increase in neurotensin release. Somatostatin (100 nM) reduced maximal stimulation with 100 nM substance P by 79%. Our results suggest that this submucosal culture system represents an entirely new model for characterizing transmitter release from enteric neurons.
Barber
D L
DL
Department of Surgery/Section of Anatomy, Yale University Medical School, New Haven, CT 06510.
Buchan
A M
AM
Leeman
S E
SE
Soll
A H
AH
D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D004285:Dogs; D007082:Ileum / Q000166:cytology* / Q000378:metabolism; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000166:cytology* / Q000378:metabolism; D009496:Neurotensin / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D005576:Colforsin; D000001:Calcimycin; D009496:Neurotensin; D013755:Tetradecanoylphorbol Acetate