TY - JOUR
T1 - Dibutyryl cGMP augments kainate-induced elevation of intracellular calcium levels but not extracellular glutamate in cultured cerebellar granule neurons
AU - Oh, Seikwan
AU - Cai, Zhengwei
AU - McCaslin, Patrick P.
PY - 1996
Y1 - 1996
N2 - These studies were designed to examine the effect of cGMP on glutamate neurotransmission. In primary cultures of cerebellar granule cells, the glutamate receptor agonists, N-methyl-D-aspartate (NMDA) and kainate, stimulate an elevation of intracellular calcium ([Ca2+](i)), the release of glutamate, the synthesis of nitric oxide (NO) and an increase in cGMP. Although it is clear that NMDA- and kainate-induced NO stimulates guanylyl cyclase, resulting in elevation of cGMP, it is unclear whether cGMP augments the NMDA-induced elevations of extracellular glutamate or [Ca2+](i) levels. We show that the membrane permeable cGMP analogue, dibutyryl cGMP (dBcGMP), slightly augments the NMDA-induced elevation of [Ca2+](i) and significantly augments the kainate-induced the elevation of [Ca2+](i) but augments neither NMDA- nor kainate-induced release of glutamate. These results suggest that cGMP has a role in maintaining the kainate and partially NMDA receptor activation. cGMP may not be involved in EAA-induced glutamate release.
AB - These studies were designed to examine the effect of cGMP on glutamate neurotransmission. In primary cultures of cerebellar granule cells, the glutamate receptor agonists, N-methyl-D-aspartate (NMDA) and kainate, stimulate an elevation of intracellular calcium ([Ca2+](i)), the release of glutamate, the synthesis of nitric oxide (NO) and an increase in cGMP. Although it is clear that NMDA- and kainate-induced NO stimulates guanylyl cyclase, resulting in elevation of cGMP, it is unclear whether cGMP augments the NMDA-induced elevations of extracellular glutamate or [Ca2+](i) levels. We show that the membrane permeable cGMP analogue, dibutyryl cGMP (dBcGMP), slightly augments the NMDA-induced elevation of [Ca2+](i) and significantly augments the kainate-induced the elevation of [Ca2+](i) but augments neither NMDA- nor kainate-induced release of glutamate. These results suggest that cGMP has a role in maintaining the kainate and partially NMDA receptor activation. cGMP may not be involved in EAA-induced glutamate release.
KW - Ca influx
KW - Cerebellar granule neurons
KW - Dibutyryl cGMP (dBcGMP)
KW - Glutamate release
UR - http://www.scopus.com/inward/record.url?scp=0030459434&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0030459434
SN - 0269-8951
VL - 24
SP - 821
EP - 823
JO - Medical Science Research
JF - Medical Science Research
IS - 12
ER -