Dopamine Inhibits TRH-Induced MAP Kinase Activation in Dispersed Rat Anterior Pituitary Cells

Ohmichi, Masahide; Koike, Koji; Nohara, A.; Kanda, Yuki; Sakamoto, T.; Zhang, Zhen Xian; Hirota, Kenji; Miyake, Akira

doi:10.1006/bbrc.1994.1749

Cited by 22 publications

(15 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since TRH is a potent factor capable of promoting both PRL secretion and synthesis (2), we considered the possibility that PrRP can also act on PRL synthesis as well as PRL release. We reported previously that TRH rapidly and transiently induced ERK activation (10,16). PrRP was almost as potent as TRH in the ability to induce ERK activation in both GH3 cells and primary cultured rat anterior pituitary cells ( Fig.…”

Section: Discussionmentioning

confidence: 77%

“…The signals transmitted through the ERK cascade lead to activation of a set of regulatory molecules that ultimately initiate cellular responses such as growth and differentiation (13)(14)(15). Recently we have shown that TRH is capable of activating ERK in pituitary organ culture (16) and in GH3 rat pituitary tumor cells (10), and that ERK might be involved in PRL secretion or synthesis (17).…”

Section: Prolactin (Prl)mentioning

confidence: 99%

See 1 more Smart Citation

Prolactin-releasing Peptide Activation of the Prolactin Promoter Is Differentially Mediated by Extracellular Signal-regulated Protein Kinase and c-Jun N-terminal Protein Kinase

Kimura¹,

Ohmichi²,

Tasaka³

et al. 2000

Journal of Biological Chemistry

View full text Add to dashboard Cite

Regulation of the mitogen-activated protein kinase (MAPK) family by prolactin-releasing peptide (PrRP) in both GH3 rat pituitary tumor cells and primary cultures of rat anterior pituitary cells was investigated. PrRP rapidly and transiently activated extracellular signalregulated protein kinase (ERK) in both types of cells. Both pertussis toxin, which inactivates G i /G o proteins, and exogenous expression of a peptide derived from the carboxyl terminus of the ␤-adrenergic receptor kinase I, which specifically blocks signaling mediated by the ␤␥ subunits of G proteins, completely blocked the PrRPinduced ERK activation, suggesting the involvement of G i /G o proteins in the PrRP-induced ERK activation. Down-regulation of cellular protein kinase C did not significantly inhibit the PrRP-induced ERK activation, suggesting that a protein kinase C-independent pathway is mainly involved. PrRP-induced ERK activation was not dependent on either extracellular Ca 2؉ or intracellular Ca 2؉ . However, the ERK cascade was not the only route by which PrRP communicated with the nucleus. JNK was also shown to be significantly activated in response to PrRP. JNK activation in response to PrRP was slower than ERK activation. Moreover, to determine whether a MAPK family cascade regulates rat prolactin (rPRL) promoter activity, we transfected the intact rPRL promoter ligated to the firefly luciferase reporter gene into GH3 cells. PrRP activated the rPRL promoter activity in a time-dependent manner. Cotransfection with a catalytically inactive form of a MAPK construct or a dominant negative JNK, partially but significantly inhibited the induction of the rPRL promoter by PrRP. Furthermore, co-transfection with a dominant negative Ets completely abolished the response of the rPRL promoter to PrRP. These results suggest that PrRP differentially activates ERK and JNK, and both cascades are necessary to elicit rPRL promoter activity in an Ets-dependent mechanism.

show abstract

Section: Discussionmentioning

confidence: 77%

Section: Prolactin (Prl)mentioning

confidence: 99%

Prolactin-releasing Peptide Activation of the Prolactin Promoter Is Differentially Mediated by Extracellular Signal-regulated Protein Kinase and c-Jun N-terminal Protein Kinase

Kimura¹,

Ohmichi²,

Tasaka³

et al. 2000

Journal of Biological Chemistry

View full text Add to dashboard Cite

show abstract

“…DA and other catecholamines have been shown to regulate ERK activity in different cells (13,21,40,60,62). Most of the studies regarding regulation of ERK by DA have been in cells of neuronal origin, where DA activates ERK proteins via a pathway that involves D 2 R, pertussis toxin-sensitive G proteins (30,62), and Ras proteins (1,30), but this is the first report that describes the pathways of ERK stimulation by DA in AEC.…”

Section: Discussionmentioning

confidence: 95%

“…DA has an inhibitory role on the ERK pathway in most cell types (40,60), although recent reports suggest that DA activates ERK proteins in Chinese ham-ster ovary (CHO) cells (62), neurons (21), and AEC (19). However, the pathways of ERK activation by DA in lung epithelial cells have not been elucidated.…”

mentioning

confidence: 99%

Dopamine activates ERKs in alveolar epithelial cells via Ras-PKC-dependent and Grb2/Sos-independent mechanisms

Guerrero

Pesce

Lecuona

et al. 2002

American Journal of Physiology-Lung Cellular and Molecular Phys

View full text Add to dashboard Cite

Recently it has been described that dopamine (DA), via dopaminergic type 2 receptors (D2R), activates the mitogen-activated protein kinase extracellular signal-regulated kinase (MAPK/ERK) proteins in alveolar epithelial cells (AEC), which results in the upregulation of Na+-K+-ATPase. In the present report, we used AEC to investigate the signaling pathway that links DA with ERK activation. Incubation of AEC with DA resulted in rapid and transient stimulation of ERK activity, which was mediated by Ras proteins and the serine/threonine kinase Raf-1. Pretreatment of AEC with Src homology 3 binding peptide, which blocks the interaction between Grb2 and Sos, did not prevent DA activation of ERK. Diacylglycerol (DAG)-dependent protein kinase C (PKC) isoenzymes, involved in the DA-mediated activation of ERK proteins as pretreatment with either bisindolylmaleimide or Ro-31-8220, prevented the phosphorylation of Elk-1, and quinpirole, a D2R activator, stimulates the translocation of PKCε. Together, the data suggest that DA activated MAPK/ERK via Ras, Raf-1 kinase, and DAG-dependent PKC isoenzymes, but, importantly and contrary to the classical model, this pathway did not involve the Grb2-Sos complex formation.

show abstract

“…phospholipase C; G protein; mitogen-activated protein kinase THE DOPAMINE-D2 receptor gene encodes two splice variants of the receptor, long and short forms (D2L and D2S), that are pharmacologically and functionally equivalent with both forms coupling equivalently to G i /G o "inhibitory" proteins (10, 28). In pituitary cells, the dopamine D2S receptor inhibits ERK1/2 activation and cell proliferation (1,13,32,37). Oppositely, in Balb/c-3T3, Chinese hamster ovarian (CHO), and C6 mesenchymal cells, the D2S receptor stimulates cell proliferation and induces tumor formation, involving calcium mobilization and ERK1/2 activation (8,16,20,26,31).…”

mentioning

confidence: 99%

Diacylglycerol and ceramide formation induced by dopamine D2S receptors via Gβγ-subunits in Balb/c-3T3 cells

Liu

Ghahremani

Banihashemi

et al. 2003

American Journal of Physiology-Cell Physiology

View full text Add to dashboard Cite

formation induced by dopamine D2S receptors via G␤␥-subunits in Balb/c-3T3 cells. Am J Physiol Cell Physiol 284: C640-C648, 2003. First published November 13, 2002 10.1152/ajpcell.00190.2002 and ceramide are important second messengers affecting cell growth, differentiation, and apoptosis. Balb/c-3T3 fibroblast cells expressing dopamine-D2S (short) receptors (Balb-D2S cells) provide a model of G protein-mediated cell growth and transformation. In Balb-D2S cells, apomorphine (EC 50 ϭ 10 nM) stimulated DAG and ceramide formation by 5.6-and 4.3-fold, respectively, maximal at 1 h and persisting over 6 h. These actions were blocked by pretreatment with pertussis toxin (PTX), implicating G i/Go proteins. To address which G proteins are involved, Balb-D2S clones expressing individual PTX-insensitive G␣ i proteins were treated with PTX and tested for apomorphine-induced responses. Neither PTX-insensitive G␣ i2 nor G␣i3 rescued D2S-induced DAG or ceramide formation. Both D2S-induced DAG and ceramide signals required G␤␥-subunits and were blocked by inhibitors of phospholipase C [1-(6-[([17␤]-3-methoxyestra-1,2,3[10]-trien17yl)amino]hexyl)-1H-pyrrole-2,5-dione (U-73122) and partially by D609]. The similar G protein specificity of D2S-induced calcium mobilization, DAG, and ceramide formation indicates a common G␤␥-dependent phospholipase C-mediated pathway. Both D2 agonists and ceramide specifically induced mitogen-activated protein kinase (ERK1/2), suggesting that ceramide mediates a novel pathway of D2S-induced ERK1/2 activation, leading to cell growth. phospholipase C; G protein; mitogen-activated protein kinase THE DOPAMINE-D2 receptor gene encodes two splice variants of the receptor, long and short forms (D2L and D2S), that are pharmacologically and functionally equivalent with both forms coupling equivalently to G i /G o "inhibitory" proteins (10, 28). In pituitary cells, the dopamine D2S receptor inhibits ERK1/2 activation and cell proliferation (1,13,32,37). Oppositely, in Balb/c-3T3, Chinese hamster ovarian (CHO), and C6 mesenchymal cells, the D2S receptor stimulates cell proliferation and induces tumor formation, involving calcium mobilization and ERK1/2 activation (8,16,20,26,31). These actions are blocked by pertussis toxin (PTX), implicating G i /G o proteins. However, the signaling pathways that mediate G i /G o -induced regulation of cell proliferation remain poorly defined.Ceramide is a novel and important second messenger involved in a wide variety of signal transduction pathways that mediate cell-specific biological responses such as cell growth, differentiation, inflammation, and apoptosis (11,12,19,22). Ceramide is produced from many sources, such as the action of sphingomyelinase (SMase) on sphingomyelin (SM) (33), de novo synthesis (27), or metabolism of other lipids (7,17). There is also a close dynamic relationship between the biosynthetic pathways for diacylglycerol (DAG) and ceramide via SM synthase, which interconverts ceramide/phosphatidylcholine (PC) into SM/DAG (22). Thus this work focused on...

show abstract

Dopamine Inhibits TRH-Induced MAP Kinase Activation in Dispersed Rat Anterior Pituitary Cells

Cited by 22 publications

References 0 publications

Prolactin-releasing Peptide Activation of the Prolactin Promoter Is Differentially Mediated by Extracellular Signal-regulated Protein Kinase and c-Jun N-terminal Protein Kinase

Prolactin-releasing Peptide Activation of the Prolactin Promoter Is Differentially Mediated by Extracellular Signal-regulated Protein Kinase and c-Jun N-terminal Protein Kinase

Dopamine activates ERKs in alveolar epithelial cells via Ras-PKC-dependent and Grb2/Sos-independent mechanisms

Diacylglycerol and ceramide formation induced by dopamine D2S receptors via Gβγ-subunits in Balb/c-3T3 cells

Contact Info

Product

Resources

About