Increase in catecholamine release and 45Ca2+ uptake induced by GABA in cultured bovine adrenal chromaffin cells.
The role of Ca2+ in GABA-evoked catecholamine (CA) release from adrenal medulla was investigated in primary cultures of bovine adrenal chromaffin cells. GABA facilitated the 45Ca2+ uptake associated with the increase of Ca release in cultured bovine adrenal chromaffin cells. The effects of GABA on both 45Ca2+ uptake and CA release were blocked by bicuculline and picrotoxin. Nifedipine reduced the 45Ca2+ uptake and CA release induced by GABA. These data support our previous suggestion that the activation of GABA receptors on adrenal chromaffin cells facilitates the Ca2+ influx through voltage-sensitive Ca2+ channels, leading to the release of CA.
D000311:Adrenal Glands / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D002132:Calcium Radioisotopes; D002395:Catecholamines / Q000378:metabolism*; D002417:Cattle; D002478:Cells, Cultured; D002838:Chromaffin System / Q000187:drug effects / Q000378:metabolism*; D009543:Nifedipine / Q000494:pharmacology; D010852:Picrotoxin / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology*
D001640:Bicuculline; D002118:Calcium; D002132:Calcium Radioisotopes; D002395:Catecholamines; D009543:Nifedipine; D010852:Picrotoxin; D005680:gamma-Aminobutyric Acid