Ongoing nicotinic and non-nicotinic inputs to inhibitory neurons in the mouse colon.
Clin Exp Pharmacol Physiol
; 28(10): 792-8, 2001 Oct.
Article
em En
| MEDLINE
| ID: mdl-11553017
ABSTRACT
1. Intracellular microelectrodes were used to record spontaneous and evoked inhibitory junction potentials (IJP) from the circular muscle layer of the mid-distal region of the mouse isolated colon in the presence of nifedipine (1 micromol/L) and hyoscine (1 micromol/L). 2. The length of the tissue preparation (> 1 cm) or the presence of the mucosa had no effect on the frequency of spontaneous IJP. 3. Hexamethonium (500 micromol/L) reduced the frequency of spontaneous IJP to approximately 70% of the control frequency, whereas D-tubocurarine (280 micromol/L) reduced the frequency to approximately 17% of control. Apamin (250 nmol/L) abolished all spontaneous IJP activity. 4. The greater inhibition of spontaneous IJP in the presence of D-tubocurarine compared with hexamethonium is discussed as a possible 'apamin-like' effect. 5. Although electrically evoked IJP (single pulse at 15 V, 0.6 msec) were not significantly affected by hexamethonium, D-tubocurarine and apamin reduced the amplitude of evoked IJP to approximately 65 and 50% of control, respectively. 6. These results suggest that the properties of spontaneous IJP cannot be inferred by a study of evoked IJP alone.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Colo
/
Antagonistas Nicotínicos
/
Inibição Neural
/
Neurônios
Limite:
Animals
Idioma:
En
Revista:
Clin Exp Pharmacol Physiol
Ano de publicação:
2001
Tipo de documento:
Article