Stimulatory effect of trans-cinnamaldehyde on noradrenaline secretion in guinea-pig ileum myenteric nerve terminals.
Life Sci
; 66(11): 981-90, 2000.
Article
em En
| MEDLINE
| ID: mdl-10724445
ABSTRACT
The effect of trans-cinnamaldehyde (CNMA) on the release of noradrenaline (NA) from nerve terminal was investigated using isolated ileal synaptosomes of guinea-pig. Release was determined as the amount of NA, quantified by h.p.l.c.-electrochemical detection, from samples incubated with CNMA minus that in parallel blanks treated with same volume of vehicle. CNMA stimulated the secretion of NA in a concentration-dependent manner from 5 microM to 50 microM, while the value of lactate dehydrogenase in the incubated medium was not influenced by CNMA. However, trans-cinnamic acid, cinnamoyl chloride and cinnamamide failed to produce similar effect. Specific action of CNMA can thus be considered. Guanethidine inhibited the release of NA by CNMA in a concentration- dependent manner. Saxitoxin attenuated the action of CNMA at concentrations sufficient to block sodium channels. The depolarizing effect of CNMA on the membrane potential was also illustrated by a concentration-dependent increase in the fluorescence of bisoxonol, a potential sensitive dye. The NA releasing action of CNMA was deleted by removal of calcium chloride from the bathing medium. This action of CNMA was also attenuated by Rp-cAMP at concentrations sufficient to inhibit the action of cyclic AMP. These findings suggest that CNMA can depolarize the membrane to result in a calcium-dependent and cyclic AMP-related release of NA from noradrenergic terminals.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Acroleína
/
Norepinefrina
/
Íleo
/
Terminações Nervosas
Limite:
Animals
Idioma:
En
Revista:
Life Sci
Ano de publicação:
2000
Tipo de documento:
Article