Analysis of homogeneous populations of anterior pituitary folliculostellate cells by laser capture microdissection and reverse transcription-polymerase chain reaction.
Pituitary folliculostellate (FS) cells are usually located between the secretory cells in the anterior pituitary, and they produce many peptides that exert a paracrine effect on hormone-producing pituitary cells. Previous approaches have been unsuccessful in obtaining homogeneous populations of FS cells. We used a combination of immunostaining with S100 protein followed by laser capture microdissection (Immuno-LCM) to obtain purified populations of rat FS cells. These cells were analyzed along with a mouse FS cell line (TtT/GF) by RT-PCR for gene expression. RT-PCR analyses showed that both FS cell populations expressed the mRNAs for glial fibrillary acidic protein, S100 protein, transforming growth factor-beta1 (TGFbeta1), TGFbeta receptor, interleukin-6, leptin, leptin receptor, pituitary adenylate cyclase-activating polypeptide (PACAP), and PACAP receptors. Both FS cell populations were negative for PRL, GH, and POMC, supporting the homogeneity of the rat FS cell population. TGFbeta1, but not PACAP-38, treatment stimulated cell proliferation in both FS cell populations. TGFbeta1 increased leptin, but not interleukin-6, mRNA expression in rat FS cells. However, TGFbeta1 inhibited leptin RNA expression in the TtT/GF cell line, as shown by RT-PCR and Northern blot analysis. These results indicate that 1) homogeneous populations of FS cells can be prepared by Immuno-LCM; 2) TGFbeta1 stimulates the proliferation of normal rat FS cells and the TtT/GF cell line; and 3) the effects of TGFbeta1 to stimulate leptin mRNA expression in rat FS cells but inhibit leptin mRNA expression in TtT/GF cells probably reflect alterations in signal transduction in the TtT/GF cell line.
Jin
L
L
Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Tsumanuma
I
I
Ruebel
K H
KH
Bayliss
J M
JM
Lloyd
R V
RV
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004210:Dissection; D005260:Female; D007150:Immunohistochemistry; D007834:Lasers; D020738:Leptin / Q000235:genetics; D009479:Neuropeptides / Q000494:pharmacology; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D010903:Pituitary Gland, Anterior / Q000166:cytology*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011920:Rats, Inbred WF; D020133:Reverse Transcriptase Polymerase Chain Reaction; D009418:S100 Proteins / Q000032:analysis; D016212:Transforming Growth Factor beta / Q000494:pharmacology
C495403:Adcyap1 protein, rat; D020738:Leptin; D009479:Neuropeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D012333:RNA, Messenger; D009418:S100 Proteins; D016212:Transforming Growth Factor beta