Adrenomedullin reduces intracellular calcium concentration in cultured hippocampal neurons / 生理学报
Acta Physiologica Sinica
; (6): 340-345, 2005.
Article
in En
| WPRIM
| ID: wpr-334166
Responsible library:
WPRO
ABSTRACT
The effects of adrenomedullin (ADM) on intracellular calcium concentration ([Ca(2+)](i)) were investigated in cultured hippocampal neurons. Changes in [Ca(2+)](i) were detected by laser scanning confocal microscopy using Fluo 3-AM as the calcium fluorescent probe. [Ca(2+)](i) was represented by relative fluorescent intensity. The results showed that: (1) ADM (0.01-1.0 micromol/L) decreased the resting [Ca(2+)](i) in a concentration-dependent manner. (2) Calcitonin gene-related peptide receptor antagonist CGRP(8-37) significantly inhibited the effects of ADM. (3) ADM significantly reduced the increase in [Ca(2+)](i) induced by high K(+). (4) ADM markedly inhibited the inositol 1,4,5-trisphosphate (IP(3))-induced increase in [Ca(2+)](i), while did not influence ryanodine-evoked increase in [Ca(2+)](i). These results suggest that ADM reduces [Ca(2+)](i) in cultured hippocampal neurons through suppressing Ca(2+) release from IP(3)-sensitive stores. Although ADM does not alter resting Ca(2+) influx, it significantly suppresses Ca(2+) influx activated by high K(+). These effects may be partly mediated by CGRP receptors. ADM in the CNS may act as a cytoprotective factor in ischemic/hypoxic conditions.
Full text:
1
Index:
WPRIM
Main subject:
Peptides
/
Pharmacology
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Calcitonin Gene-Related Peptide
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Inositol 1,4,5-Trisphosphate
/
Cells, Cultured
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Calcium
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Rats, Sprague-Dawley
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Receptors, Calcitonin Gene-Related Peptide
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Cell Biology
/
Embryo, Mammalian
Limits:
Animals
Language:
En
Journal:
Acta Physiologica Sinica
Year:
2005
Type:
Article