Second messengers associated with the action of AII and dopamine D2 receptors in anterior pituitary. Relationship with prolactin secretion.
We have shown that DA receptors of the D2 subtype inhibit prolactin release by several mechanisms. DA receptors inhibit cyclic AMP production through a GTP binding protein sensitive to the Bordetella pertussis toxin. However, this mechanism cannot be involved in the blockade of the AII stimulated prolactin secretion by DA. This blockade is probably partly due to the inhibition of the AII-stimulated inositol phosphate production by DA. This inhibition is also sensitive to the Bordetella pertussis toxin. The toxin is able to ADP-ribosylate three substrates in anterior pituitary cells (39, 40 and 41 kDa). In addition, we show here that AII receptors inhibit adenylate cyclase of anterior pituitary cell homogenates, but not in intact cells.
Bockaert
J
J
Centre CNRS-INSERM de Pharmacologie-Endocrinologie, Montpellier, France.
Journot
L
L
Enjalbert
A
A
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D037361:Adenylate Cyclase Toxin; D000067956:Adenylyl Cyclase Inhibitors; D000818:Animals; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism; D004298:Dopamine / Q000494:pharmacology*; D005260:Female; D019204:GTP-Binding Proteins / Q000378:metabolism; D007295:Inositol Phosphates / Q000378:metabolism; D037342:Pertussis Toxin; D010903:Pituitary Gland, Anterior / Q000378:metabolism*; D011388:Prolactin / Q000378:metabolism*; D051381:Rats; D011945:Receptors, Angiotensin / Q000187:drug effects / Q000502:physiology*; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology*; D012636:Secretory Rate; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D037361:Adenylate Cyclase Toxin; D000067956:Adenylyl Cyclase Inhibitors; D007295:Inositol Phosphates; D011945:Receptors, Angiotensin; D011954:Receptors, Dopamine; D010566:Virulence Factors, Bordetella; D000246:Adenosine Diphosphate Ribose; D011388:Prolactin; D000242:Cyclic AMP; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D004298:Dopamine