Effect of changes in [Ca++] on responses of the isolated rat stomach to transmural stimulation
Bettini, V.; Cessi, C.; Legrenzi, E.; Sandini, C.
Bollettino della Societa Italiana di Biologia Sperimentale 53(10): 840-844
1977
ISSN/ISBN: 0037-8771 PMID: 588356 Document Number: 119994
Isolated rat stomach preparations were used, applying a transmural 1-3 ms stimulus. The preparation was oxygenated with a gaseous O2/CO2 mixture using a Grass electric stimulator. An increase in Ca2+ in the medium from 2.54 to 5.08 mM always increased the amplitude of contraction of the preparation on transmural stimulation. When an isolated and denervated rat stomach preparation was used in standard Krebs solution, the addition of 0.1 .mu.g/ml acetylcholine (ACH) increased the tone of the preparation. In the denervated preparation the Ca2+ increased the effect of exogenous ACH, but to a lesser extent than the contractile response of the stomach to transmural stimulation. The increase in the output of the mediator is accompanied by an increase in the contractile response.