Involvement of calcium in the release of immunoreactive beta-endorphin-like peptide from dispersed cells of the neurointermediate lobe of the rat pituitary gland.
The presence of Ca2+ in the incubation medium was required for stimulation of the release of the immunoreactive beta-endorphin-like peptide (IR-beta-EP) from the dispersed cells of the neurointermediate lobe of rat pituitary gland by adenosine 3',5'-monophosphate (cAMP) analogs, a phosphodiesterase inhibitor, L-isoproterenol, cholera toxin and forskolin. The basal release observed in the absence of the stimulants was also dependent on the addition of Ca2+. A calcium antagonist (verapamil) inhibited the effects of the stimulants. A calcium ionophore (A23187) enhanced the release of IR-beta-EP, but did not stimulate the formation of cAMP. These findings suggest that Ca2+ has the essential role in the release of beta-endorphin from the neurointermediate lobe of rat pituitary gland.
Sakoda
Y
Y
Munemura
M
M
Furuki
Y
Y
Hatada
Y
Y
Maeyama
M
M
Miyamoto
E
E
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000502:physiology*; D002772:Cholera Toxin / Q000494:pharmacology; D005576:Colforsin; D000242:Cyclic AMP / Q000378:metabolism; D004224:Diterpenes / Q000494:pharmacology; D004723:Endorphins / Q000378:metabolism*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D010902:Pituitary Gland / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D013806:Theophylline / Q000494:pharmacology; D014700:Verapamil / Q000494:pharmacology; D001615:beta-Endorphin
D004224:Diterpenes; D004723:Endorphins; D005576:Colforsin; D000001:Calcimycin; D001615:beta-Endorphin; D003994:Bucladesine; D002772:Cholera Toxin; D013806:Theophylline; D014700:Verapamil; D000242:Cyclic AMP; D007545:Isoproterenol; D002118:Calcium; D015056:1-Methyl-3-isobutylxanthine