Differential dopamine-induced prolactin mRNA levels in various prolactin-secreting cell (sub)populations.
We have examined the effects of dopamine on prolactin gene expression using quantitative in-situ hybridization histochemistry in different pituitary cell (sub)populations separated according to their density on a discontinuous Percoll gradient. Administration of dopamine resulted in a drastic reduction in hybridization of 35S-labelled DNA probe complementary to prolactin mRNA in total pituitary cells and in lactotrophs with low density. In contrast, dopamine significantly stimulated mRNA accumulation in prolactin-secreting cells with high density compared with other cell layers. The combined use of Percoll gradient and quantitative in-situ hybridization is a valuable and sensitive method with which to examine prolactin-secreting cell response to a given stimulation. Prolactin-secreting cells with high and low density clearly show functional heterogeneity in their response to dopamine.
Kazemzadeh
M
M
Department of Pharmacology, Medical School, Free University of Brussels, Belgium.
Velkeniers
B
B
Herregodts
P
P
Collumbien
R
R
Finné
E
E
Derde
M P
MP
Vanhaelst
L
L
Hooghe-Peters
E L
EL
D000818:Animals; D002478:Cells, Cultured; D004298:Dopamine / Q000502:physiology*; D005260:Female; D015870:Gene Expression / Q000502:physiology*; D009693:Nucleic Acid Hybridization; D010903:Pituitary Gland, Anterior / Q000166:cytology / Q000502:physiology*; D011388:Prolactin / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis*; D051381:Rats; D011919:Rats, Inbred Strains
D012333:RNA, Messenger; D011388:Prolactin; D004298:Dopamine