title: Cell specific distribution of guanine nucleotide-binding regulatory proteins in rat pituitary tumour cell lines.
abstract: To investigate the effects of guanine nucleotide-binding regulatory proteins (G proteins) on hormonal regulation of prolactin (PRL) synthesis and secretion, the qualitative distribution of G protein alpha-subunits and their mRNAs was studied in three functionally different pituitary tumour cell lines (GH cells) and normal rat pituitary tissue. Levels of basal and modulated adenylyl cyclase (AC) and phospholipase C (PLC) activities are also included. GH cells and pituitary tissue contained various amounts of mRNAs and protein for Gs alpha, Gi-2 alpha, Gi-3 alpha and Go alpha, while mRNA for Gi-1 alpha was only detected in normal pituitary tissue. Gz alpha/Gx alpha mRNA was expressed in all pituitary cell lines as well as in pituitary tissue. Go alpha mRNA and Gz alpha/G x alpha mRNA displayed size heterogeneity. These findings may have importance in the understanding of hormone regulation of second messenger systems.
authors.affiliation: Institute of Medical Biochemistry, University of Oslo, Norway.
authors.forename: E J
authors.initials: EJ
authors.lastname: Paulssen
authors.forename: R H
authors.initials: RH
authors.lastname: Paulssen
authors.forename: T B
authors.initials: TB
authors.lastname: Haugen
authors.forename: K M
authors.initials: KM
authors.lastname: Gautvik
authors.forename: J O
authors.initials: JO
authors.lastname: Gordeladze
mesh_terms: D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D005260:Female; D019204:GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D015151:Immunoblotting; D009928:Organ Specificity; D010902:Pituitary Gland / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013973:Thyrotropin-Releasing Hormone / Q000378:metabolism; D014407:Tumor Cells, Cultured; D010738:Type C Phospholipases / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D013973:Thyrotropin-Releasing Hormone; D010738:Type C Phospholipases; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases