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Yang Q, Battistini B, Pelletier S, Sirois P. Inhibition of basal and stimulated release of endothelin-1 from guinea pig tracheal epithelial cells in culture by beta 2-adrenoceptor agonists and cyclic AMP enhancers. Inflammation 2007; 30:136-47. [PMID: 17620004 DOI: 10.1007/s10753-007-9030-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The effects of cyclic AMP-related compounds and beta adrenoceptor agonists on the basal and lipopolysaccharide (LPS)-stimulated release of endothelin-1 (ET-1) from guinea-pig tracheal epithelial cells (GPTEpCs) in culture were studied. Forskolin (a potent activator of adenylyl cyclase), 8-bromo-cyclic AMP (a cyclic AMP analogue), salbutamol and salmeterol (two beta 2-adrenoceptor agonists), were used to increase cyclic AMP levels. Cultured GPTEpCs released ET-1 continuously over a 24 h incubation period. The values reached 1,938 +/- 122 pg/mg of total cell proteins after 24 h. LPS (10 microg/ml) significantly stimulated the release of ET-1 by 1.6- to 1.8-fold, up to 1,262 +/- 56 pg/mg total cell proteins after an 8 h incubation period. Compound 8-bromo-cyclic AMP (10(-5), 10(-4) and 10(-3) M) reduced the basal release of ET-1 from GPTEpCs by up to 31% (P < 0.01) and the LPS stimulated release by up to 42% (P < 0.05), after an 8 h incubation period. Forskolin (10(-6), 10(-5) and 10(-4) M) also inhibited the basal release of ET-1 by up to 28% (P < 0.05) and LPS-stimulated release of ET-1 by up to 50% (P < 0.05), after an 8 h incubation period. At the concentration of 10(-5) M, forskolin increased cyclic AMP levels in GPTEpCs by 17-fold (P < 0.001) in the medium, 15 min after the beginning of the incubation. Salbutamol (10(-8) to 10(-6) M) had no effect on the basal production and release of ET-1 after 8 h. Conversely, this short acting beta 2-adrenoceptor agonist significantly reduced LPS-mediated increase of ET-1 production by up to 55% (P < 0.05) after an 8 h incubation period. Salmeterol (10(-9) M to 10(-5) M) inhibited basal and LPS-stimulated production and release of ET-1 after an 8 h incubation period (between 44 and 51%, P < 0.01). Both salbutamol and salmeterol (10(-6) M) increase cyclic AMP levels by five- and twofold, respectively (P < 0.05). In summary, these observations indicate that beta 2-adrenoceptor agonists or cyclic AMP enhancers can modulate both basal and more markedly, the enhanced production of ET-1 from LPS-activated guinea pig airway EpCs. In addition, these compounds increase cyclic AMP levels in the cells. It is suggested that there is a correlation between cyclic AMP increase and inhibition of ET-1 release by guinea pig airway EpCs. Since ET-1 production was shown to be elevated in asthmatic subjects and in patients suffering from other inflammatory lung disorders, the inhibition of its production by beta adrenoceptor agonists, such as salbutamol and salmeterol, could be added to their therapeutical benefits.
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Affiliation(s)
- Quan Yang
- Institute of Pharmacology of Sherbrooke, Medical School, University of Sherbrooke, Sherbrooke, QC, J1H 5N4, Canada
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2
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McCreary AC, Glennon JC, Ashby CR, Meltzer HY, Li Z, Reinders JH, Hesselink MB, Long SK, Herremans AH, van Stuivenberg H, Feenstra RW, Kruse CG. SLV313 (1-(2,3-dihydro-benzo[1,4]dioxin-5-yl)-4- [5-(4-fluoro-phenyl)-pyridin-3-ylmethyl]-piperazine monohydrochloride): a novel dopamine D2 receptor antagonist and 5-HT1A receptor agonist potential antipsychotic drug. Neuropsychopharmacology 2007; 32:78-94. [PMID: 16710314 DOI: 10.1038/sj.npp.1301098] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Combined dopamine D(2) receptor antagonism and serotonin (5-HT)(1A) receptor agonism may improve efficacy and alleviate some side effects associated with classical antipsychotics. The present study describes the in vitro and in vivo characterization of 1-(2,3-dihydro-benzo[1,4]dioxin-5-yl)-4-[5-(4-fluoro-phenyl)-pyridin-3-ylmethyl]-piperazine monohydrochloride (SLV313), a D(2/3) antagonist and 5-HT(1A) agonist. SLV313 possessed high affinity at human recombinant D(2), D(3), D(4), 5-HT(2B), and 5-HT(1A) receptors, moderate affinity at 5-HT(7) and weak affinity at 5-HT(2A) receptors, with little-no affinity at 5-HT(4), 5-HT(6), alpha(1), and alpha(2) (rat), H(1) (guinea pig), M(1), M(4), 5-HT(3) receptors, and the 5-HT transporter. SLV313 had full agonist activity at cloned h5-HT(1A) receptors (pEC(50)=9.0) and full antagonist activity at hD(2) (pA(2)=9.3) and hD(3) (pA(2)=8.9) receptors. In vivo, SLV313 antagonized apomorphine-induced climbing and induced 5-HT(1A) syndrome behaviors and hypothermia, the latter behaviors being antagonized by the 5-HT(1A) antagonist WAY100635. In a drug discrimination procedure SLV313 induced full generalization to the training drug flesinoxan and was also antagonized by WAY100635. In the nucleus accumbens SLV313 reduced extracellular 5-HT and increased dopamine levels in the same dose range. Acetylcholine and dopamine were elevated in the hippocampus and mPFCx, the latter antagonized by WAY100635, suggesting possible 5-HT(1A)-dependent efficacy for the treatment of cognitive and attentional processes. SLV313 did not possess cataleptogenic potential (up to 60 mg/kg p.o.). The number of spontaneously active dopamine cells in the ventral tegmental area was reduced by SLV313 and clozapine, while no such changes were seen in the substantia nigra zona compacta following chronic administration. These results suggest that SLV313 is a full 5-HT(1A) receptor agonist and full D(2/3) receptor antagonist possessing characteristics of an atypical antipsychotic, representing a potential novel treatment for schizophrenia.
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Memo M, Pizzi M, Belloni M, Benarese M, Spano P. Activation of Dopamine D2 Receptors Linked to Voltage-Sensitive Potassium Channels Reduces Forskolin-Induced Cyclic AMP Formation in Rat Pituitary Cells. J Neurochem 2006; 59:1829-35. [PMID: 1357100 DOI: 10.1111/j.1471-4159.1992.tb11016.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
3,4-Dihydroxyphenylethylamine (dopamine) D2 receptor agonists, including BHT 920 and bromocriptine, and the potassium channel opener minoxidil share the property of hyperpolarizing the plasma membrane by activating voltage-dependent potassium channels. These drugs were tested for their ability to inhibit the cyclic AMP formation induced by forskolin either in intact or in broken pituitary cells. In contrast to bromocriptine, which was active in both experimental systems, BHT 920 and minoxidil inhibited the forskolin-induced cyclic AMP formation in intact-cell but not in broken-cell preparations. The effects of BHT 920 were (a) concentration dependent, with a calculated IC50 of 0.7 microM, (b) dopaminergic in nature, being specifically antagonized by sulpiride, (c) not additive with those induced by minoxidil, and (d) less effective in the presence of potassium channel blockers, such as 4-aminopyridine and tetraethylammonium. These data indicate that the inhibition of forskolin-induced cyclic AMP formation by BHT 920 in intact pituitary cells is not a primary consequence of receptor occupation, but a late event, possibly related to the opening of voltage-dependent potassium channels elicited by this drug through the activation of a subtype of dopamine D2 receptors uncoupled to adenylyl cyclase.
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Affiliation(s)
- M Memo
- Department of Biomedical Sciences and Biotechnologies, School of Medicine, University of Brescia, Italy
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4
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Zhang A, Kan Y, Li F. Recent advances towards the discovery of dopamine receptor ligands. Expert Opin Ther Pat 2006. [DOI: 10.1517/13543776.16.5.587] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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5
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Pelletier S, Dubé J, Villeneuve A, Gobeil F, Bernier SG, Battistini B, Guillemette G, Sirois P. Adenosine induces cyclic-AMP formation and inhibits endothelin-1 production/secretion in guinea-pig tracheal epithelial cells through A(2B) adenosine receptors. Br J Pharmacol 2000; 129:243-50. [PMID: 10694229 PMCID: PMC1571824 DOI: 10.1038/sj.bjp.0702999] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
1. The adenosine receptor subtype mediating adenosine 3' : 5'-cyclic monophosphate (cyclic AMP) formation and the effect of its activation on endothelin-1 (ET-1) secretion were studied in primary cultures of tracheal epithelial cells. 2. Adenosine analogues showed the following rank order of potency (pD(2) value) and intrinsic activity on the generation of cyclic AMP by tracheal epithelial cells: 5'-N-ethylcarboxyamidoadenosine (NECA, A(1)/A(2A)/A(2B), pD(2): 5.44+/-0.16)>adenosine (ADO, non selective, pD(2): 4.99+/-0. 09; 71+/-9% of NECA response) >/=2-Cl-adenosine (2CADO, non selective, pD(2): 4.72+/-0.14; 65+/-9% of NECA response)>>>CGS21680 (A(2A); inactive at up to 100 microM). 3. Cyclic AMP formation stimulated by NECA in guinea-pig tracheal epithelial cells was inhibited by adenosine receptor antagonist with the following order of apparent affinity (pA(2) value): Xanthine amine congeners (XAC, A(2A)/A(2B), 7.89+/-0.22)>CGS15943 (A(2A)/A(2B), 7.24+/-0. 26)>ZM241385 (A(2A), 6.69+/-0.14)>DPCPX (A(1), 6.51+/-0. 14)>3n-propylxanthine (weak A(2B), 4.30+/-0.10). This rank order of potency is typical for A(2B)-adenosine receptor. 4. Adenosine decreased basal and LPS-stimulated irET production in a concentration-dependent manner. Moreover, NECA but not CGS21680 inhibited LPS-induced irET production. 5. The inhibitory effect of NECA on LPS-induced irET production was reversed by XAC (pA(2)=8.84+/-0. 12) and DPCPX (pA(2)=8.10+/-0.22). 6. These results suggested that adenosine increased cyclic AMP formation and inhibited irET production/secretion by guinea-pig tracheal epithelial cells through the activation of a functional adenosine receptor that is most likely the A(2B) subtype. This adenosine receptor may be involved in the regulation of the level of ET-1 production/secretion by guinea-pig tracheal epithelial cells in physiological as well as in pathophysiological conditions.
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Affiliation(s)
- S Pelletier
- Institut de Pharmacologie de Sherbrooke, Faculté de Médecine, Université de Sherbrooke, Sherbrooke (PQ) Canada
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6
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Oiry C, Pannequin J, Cormier A, Galleyrand JC, Martinez J. L-365,260 inhibits in vitro acid secretion by interacting with a PKA pathway. Br J Pharmacol 1999; 127:259-67. [PMID: 10369481 PMCID: PMC1565992 DOI: 10.1038/sj.bjp.0702505] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
The aim of this study was to analyse the antisecretory mechanism of L-365,260 in vitro in isolated rabbit gastric glands. We showed that compound L-365,260, described as a non-peptide specific competitive CCK-B receptor antagonist, was able to dose-dependently inhibit [14C]-aminopyrine accumulation induced by histamine (10(-4) M), carbachol (5x10(-5) M), 3-isobutyl-1-methyl-xanthine (IBMX) (5x10(-6) M) and forskolin (5x10(-7) M) with similar IC50 values respectively of 1.1+/-0.6x10(-7) M, 1.9+/-1.2x10(-7) M, 4.2+/-2.0x10(-7) M and 4.0+/-2.8x10(-7) M. We showed that L-365,260 acted beyond receptor activation and production of intracellular second messengers and that it had no action on the H+/K+ -ATPase. We found that L-365,260 inhibited cyclic AMP-induced [14C]-aminopyrine accumulation in digitonin-permeabilized rabbit gastric glands, suggesting that this compound acted, at least in part, as an inhibitor of the cyclic AMP-dependent protein kinase (PKA) pathway.
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Affiliation(s)
- Catherine Oiry
- Laboratoire des Amino Acides, Peptides et Protéines (L.A.P.P.) UMR CNRS 5810, Faculté de Pharmacie, 15 Av. C. Flahault, 34060 Montpellier, France
| | - Julie Pannequin
- Laboratoire des Amino Acides, Peptides et Protéines (L.A.P.P.) UMR CNRS 5810, Faculté de Pharmacie, 15 Av. C. Flahault, 34060 Montpellier, France
| | - Anne Cormier
- Laboratoire des Amino Acides, Peptides et Protéines (L.A.P.P.) UMR CNRS 5810, Faculté de Pharmacie, 15 Av. C. Flahault, 34060 Montpellier, France
| | - Jean-Claude Galleyrand
- Laboratoire des Amino Acides, Peptides et Protéines (L.A.P.P.) UMR CNRS 5810, Faculté de Pharmacie, 15 Av. C. Flahault, 34060 Montpellier, France
| | - Jean Martinez
- Laboratoire des Amino Acides, Peptides et Protéines (L.A.P.P.) UMR CNRS 5810, Faculté de Pharmacie, 15 Av. C. Flahault, 34060 Montpellier, France
- Author for correspondence:
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7
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Briand SI, Bellemare JM, Bernier SG, Guillemette G. Study on the functionality and molecular properties of the AT4 receptor. Endocr Res 1998; 24:315-23. [PMID: 9888503 DOI: 10.3109/07435809809032611] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Whereas the role of angiotensin II (Ang II) has been clarified in numerous tissues and cell types, the physiological relevance of its C-terminal (3-8) degradation fragment, angiotensin IV (Ang IV), is unclear. Previously, we characterized a specific binding site for Ang IV in the bovine adrenal cortex and on bovine aortic endothelial cells (BAEC). In the present study, we tried to assess the functionality and mechanism of action of this receptor for Ang IV (AT4 receptor). Our results revealed that none of the classical second messengers (i.e., cAMP, Ca2+, inositol phosphates, nitric oxide or arachidonic acid derivatives) was modified significantly during acute (less than 1 h) stimulation of cells with Ang IV. Under normal culture conditions, BAEC efficiently internalized 125I-Ang IV. After a 2 h incubation at 37 degrees C, acid-resistant binding corresponded to about 50% of total cell-associated radioactivity. This rapid internalization process suggests that the AT4 receptor is a functional protein. With a photoaffinity labeling approach, we revealed some properties of the AT4 receptor that are consistent with those of a growth factor or cytokine receptor.
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MESH Headings
- Angiotensin II/analogs & derivatives
- Angiotensin II/metabolism
- Angiotensin II/pharmacology
- Animals
- Aorta, Thoracic/cytology
- Aorta, Thoracic/metabolism
- Calcium/metabolism
- Cattle
- Cells, Cultured
- Intracellular Membranes/metabolism
- Molecular Weight
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/metabolism
- Osmolar Concentration
- Photoaffinity Labels
- Receptors, Angiotensin/chemistry
- Receptors, Angiotensin/metabolism
- Receptors, Angiotensin/physiology
- Second Messenger Systems/physiology
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Affiliation(s)
- S I Briand
- Department of Pharmacology, Faculty of Medecine, Université de Sherbrooke, Québec, Canada
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8
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Richard DE, Laporte SA, Bernier SG, Leduc R, Guillemette G. Desensitization of AT1 receptor-mediated cellular responses requires long term receptor down-regulation in bovine adrenal glomerulosa cells. Endocrinology 1997; 138:3828-35. [PMID: 9275071 DOI: 10.1210/endo.138.9.5409] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Angiotensin II (Ang II) regulates aldosterone production in bovine adrenal glomerulosa cells by interacting with the AT1 receptor. This receptor is coupled to a G protein that controls the activity of phospholipase C. With a primary culture of bovine adrenal glomerulosa cells, we evaluated the desensitization of cellular responses after pretreatment with Ang II. When cells were pretreated for 30 min with 1 microM Ang II at 37 C, we observed a 48% loss of [125I]Ang II-binding activity. Scatchard analysis revealed that this decreased binding activity corresponded to a 53% loss of the total number of binding sites. This phenomenon was time dependent, with a t(1/2) of 20 min, and a maximal loss of 76% of the total binding sites was observed after 14 h. A time-dependent decrease in AT1 receptor messenger RNA levels was also observed after pretreatment with 1 microM Ang II for 12-24 h. Taken together, these results are interpreted as a down-regulation of the AT1 receptor. Desensitization of phospholipase C activity under similar conditions was, however, a slower process, with a t(1/2) of 9 h and a maximal response reduction of 83% observed after 24 h. Dose-response experiments indicated that maximal phospholipase C desensitization was obtained in the presence of 1 microM Ang II, with an EC50 of 90 nM. The desensitization was of a homologous nature, as a 24-h pretreatment with Ang II did not affect bradykinin-induced inositol phosphate production. A 24-h pretreatment with 1 microM Ang II also significantly desensitized the steroidogenic effect of Ang II and the potentiating effect of Ang II on ACTH-induced cAMP production. Lower concentrations of Ang II (10 nM) did not produce any desensitizing effect on these two parameters. This study provides evidence that glomerulosa cells are functionally resistant to short term desensitization of the AT1 receptor and that long term down-regulation with high concentrations of Ang II is needed to desensitize AT1-mediated cellular responses.
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Affiliation(s)
- D E Richard
- Department of Pharmacology, Faculty of Medicine, University of Sherbrooke, Quebec, Canada
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9
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Kuipers W, Kruse CG, van Wijngaarden I, Standaar PJ, Tulp MT, Veldman N, Spek AL, IJzerman AP. 5-HT1A-versus D2-receptor selectivity of flesinoxan and analogous N4-substituted N1-arylpiperazines. J Med Chem 1997; 40:300-12. [PMID: 9022796 DOI: 10.1021/jm960496o] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We investigated the structural requirements for high 5-HT1A affinity of the agonist flesinoxan and its selectivity versus D2 receptors. For this purpose a series of arylpiperazine congeners of flesinoxan were synthesized and evaluated for their ability to displace [3H]-8-OH-DPAT and [3H]spiperone from their specific binding sites in rat frontal cortex homogenates and rat striatum, respectively. Variations were made in the N4-substituent and the arylpiperazine region. Effects of N4-substitution in the investigated compounds appeared to be quite similar for 5-HT1A- and D2-receptor affinity. Lipophilicity at a distance of four carbon atoms from the piperazine N4 atom seems to be the main contributing factor to affinity for both receptors. Our data show that the amide group in the flesinoxan N4-substituent is unlikely to interact with the 5-HT1A receptor but, instead, acts as a spacer. In contrast to the structure-affinity relationships (SARs) of the N4-substituents, selectivity for 5-HT1A versus D2 receptors was gained by the arylpiperazine substitution pattern of flesinoxan. Restriction of flexibility of the N4-(benzoylamino)ethyl substituent and its effect on 5-HT1A-receptor affinity and activity were also studied. Our data show that in the bioactive conformation, the N4-[(p-fluorobenzoyl)amino]ethyl substituent is probably directed anti-periplanar relative to the HN4 atom. These results were used to dock flesinoxan (1) and two of its congeners (27 and 33) into a model of the 5-HT1A receptor that we previously reported. Amino acid residues surrounding the N4-[(p-fluorobenzoyl)amino]ethyl substituent of flesinoxan and its congeners are also present in D2 receptors. In contrast, several residues that contact the benzodioxane moiety differ from those in D2 receptors. These observations from the 3D model agree with the 5-HT1A SAR data and probably account for the selectivity of flesinoxan versus D2 receptors.
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Affiliation(s)
- W Kuipers
- Department of Medicinal Chemistry, Solvay Pharmaceuticals Research Laboratories, DA Weesp, The Netherlands.
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10
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Lezcano NE, De Barioglio SR, Celis ME. alpha-MSH changes cyclic AMP levels in rat brain slices by an interaction with the D1 dopamine receptor. Peptides 1995; 16:133-7. [PMID: 7716065 DOI: 10.1016/0196-9781(94)00157-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The exposure of rat brain slices containing caudate putamen and accumbens nuclei to alpha-MSH or dopamine (DA) results in an increase in cyclic AMP (cAMP) levels. When tissues are compared with those containing both alpha-MSH and DA, a reduction in the cyclic nucleotide is observable. This study was carried out to determine whether variations in tissular cAMP levels induced by alpha-MSH might be explained by an interaction between the peptide and some dopaminergic receptors. Therefore, we measured cAMP in tissues and medium in response to alpha-MSH in the presence of haloperidol, the selective D1 (SCH 23390) or D2 (sulpiride) antagonists, or the selective D1 (SKF 38393) or D2 (bromocriptine) agonists. Haloperidol by itself induced no changes either in the cAMP content or in the cAMP efflux to the medium. When slices were exposed to alpha-MSH and haloperidol, the latter blocked the alpha-MSH effect of inducing an increase in the content of cAMP. None of the specific antagonists (at the administered doses) induced changes in the content of cAMP when compared with the control group. The presence of SCH 23390 in the incubation medium together with alpha-MSH yielded a reduction in cAMP levels compared with those incubated with alpha-MSH. A slight stimulatory effect on cAMP formation was observed when the dopaminergic agonists (SKF 38393 10 microM) were used. We conclude that alpha-MSH interacts with the D1 dopamine receptor, changing the cAMP levels in striatum and accumbens nuclei.
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Affiliation(s)
- N E Lezcano
- Department of Pharmacology, Facultad de Ciencias Quimicas, Universidad Nacional de Cordoba, Argentina
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11
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Hol EM, Gispen WH, Bär PR. ACTH-related peptides: receptors and signal transduction systems involved in their neurotrophic and neuroprotective actions. Peptides 1995; 16:979-93. [PMID: 7479345 DOI: 10.1016/0196-9781(95)00017-e] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
ACTH-related peptides are promising neurotrophic and neuroprotective agents, as demonstrated in many in vivo and in vitro studies. They accelerate nerve repair after injury, improving both sensor and motor function. Furthermore, ACTH-related peptides have neuroprotective properties against cisplatin- and taxol-induced neurotoxicity, they improve neuronal function in animals with neuropathy due to experimental diabetes, and they prevent degeneration of myelinated axons in rats suffering from experimental allergic neuritis, a model of peripheral demyelinating neuropathy. Studies in neuronal cultures have corroborated these clinical observations and serve to investigate the mechanism of action of the ACTH-related peptide effects. This paper reviews both in vitro and in vivo effects and emphasizes the mechanism of action. Recent data on melanotrophic receptors and signal transduction systems will be discussed in this context.
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Affiliation(s)
- E M Hol
- Department of Neurology, Rudolf Magnus Institute for Neurosciences, Utrecht University, The Netherlands
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12
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Hol EM, Gispen WH, Bär PR. Involvement of calcium and cAMP in the mechanism of action of two melanocortins: alpha MSH and an ACTH-(4-9) analogue. Ann N Y Acad Sci 1994; 739:324-7. [PMID: 7832486 DOI: 10.1111/j.1749-6632.1994.tb19836.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- E M Hol
- Department of Neurology, Rudolf Magnus Institute, Utrecht University, The Netherlands
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13
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Hol EM, Sodaar P, Bär PR. Dorsal root ganglia as an in vitro model for melanocortin-induced neuritogenesis. Pharmacological and mechanistic aspects. Ann N Y Acad Sci 1994; 739:74-86. [PMID: 7832498 DOI: 10.1111/j.1749-6632.1994.tb19808.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- E M Hol
- Department of Neurology, Rudolf Magnus Institute, Utrecht University, The Netherlands
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14
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Hol EM, Verhage M, Gispen WH, Bär PR. The role of calcium and cAMP in the mechanism of action of two melanocortins: alpha MSH and the ACTH4-9 analogue Org 2766. Brain Res 1994; 662:109-16. [PMID: 7859062 DOI: 10.1016/0006-8993(94)90802-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Melanocortins accelerate functional recovery after nerve crush and enhance neurite outgrowth in vitro. To get more insight in the mechanism of action of melanocortins, we studied the effects of two neurotrophic peptides: alpha-melanocyte-stimulating hormone (alpha MSH) and an adrenocorticotropin4-9 analogue Org 2766 on second messengers in cultures of spinal cord (SC), dorsal root ganglion (DRG) and Schwann cells. alpha MSH (10 microM) enhanced the forskolin-induced cAMP production in SC- (45%) and in DRG-cells (35%). Org 2766 (1 microM) induced an increase in cAMP only in SC-cells (39%). The peptides did not affect the cAMP levels in Schwann cells. Neither peptide evoked significant changes in the intracellular free calcium concentration ([Ca2+]i) in batch-measurements of all cell types, however, Ca(2+)-imaging revealed an infrequent occurrence of large [Ca2+]i-elevations in individual SC-neurons. The results indicate that SC- and DRG-cells are targets for both peptides, while Schwann cells are not or exploit different pathways. We observed for alpha MSH that cAMP production always coincides with outgrowth stimulation, whereas for Org 2766 cAMP production and outgrowth stimulation appear not causally related. These differences in second messenger stimulation could be explained by receptor heterogeneity. We suggest that alpha MSH and Org 2766 act through different receptors, each with its own signalling pathways.
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Affiliation(s)
- E M Hol
- Department of Neurology, Rudolf Magnus Institute for Neurosciences, Utrecht University, The Netherlands
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15
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Florijn WJ, Mulder AH, Versteeg DH, Gispen WH. Adrenocorticotropin/alpha-melanocyte-stimulating hormone (ACTH/MSH)-like peptides modulate adenylate cyclase activity in rat brain slices: evidence for an ACTH/MSH receptor-coupled mechanism. J Neurochem 1993; 60:2204-11. [PMID: 8388034 DOI: 10.1111/j.1471-4159.1993.tb03506.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The regulation of adenylate cyclase activity by adrenocorticotropin/alpha-melanocyte-stimulating hormone (ACTH/MSH)-like peptides was investigated in rat brain slices using a superfusion method. Adenylate cyclase activity was concentration-dependently increased by ACTH-(1-24), alpha-MSH (EC50 values 16 and 6 nM, respectively), and [Nle4,D-Phe7]alpha-MSH (EC50 value 1.6 nM), in the presence of forskolin (1 microM, optimal concentration). 1-9-Dideoxyforskolin did not augment the response of adenylate cyclase to ACTH-(1-24). Various peptide fragments were tested for their ability to enhance [3H]cyclic AMP production. [Nle4,D-Phe7]alpha-MSH increased [3H]cyclic AMP formation with a maximal effect of 30% and was more potent than ACTH-(1-24), ACTH-(1-16)-NH2, alpha-MSH, ACTH-(1-13)-NH2, [MetO4]alpha-MSH, [MetO2(4),D-Lys8,Phe9]ACTH-(4-9), ACTH-(7-16)-NH2, ACTH-(1-10), and ACTH-(11-24), in order of potency. This structure-activity relationship resembles that found for the previously described peptide-induced display of excessive grooming. ACTH-(1-24) stimulated adenylate cyclase activity in both striatal (maximal effect, approximately 20%) and septal slices (maximal effect, approximately 40%), but not in hippocampal or cortical slices. Lesioning of the dopaminergic projections to the striatum did not result in a diminished effect of [Nle4,D-Phe7]alpha-MSH on [3H]cyclic AMP accumulation, which indicates that the ACTH/MSH receptor-stimulated adenylate cyclase is not located on striatal dopaminergic terminals. ACTH-(1-24) did not affect the dopamine D1 or D2 receptor-mediated modulation of adenylate cyclase activity.(ABSTRACT TRUNCATED AT 250 WORDS)
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MESH Headings
- 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine/pharmacology
- 3,4-Dihydroxyphenylacetic Acid/metabolism
- Adenylyl Cyclases/metabolism
- Adrenocorticotropic Hormone/analogs & derivatives
- Adrenocorticotropic Hormone/pharmacology
- Animals
- Brain/drug effects
- Brain/enzymology
- Brain/metabolism
- Chromatography, High Pressure Liquid
- Colforsin/analogs & derivatives
- Colforsin/pharmacology
- Cyclic AMP/metabolism
- Desipramine/pharmacology
- Dopamine/metabolism
- Dopamine/pharmacology
- Dose-Response Relationship, Drug
- Ergolines/pharmacology
- In Vitro Techniques
- Kinetics
- Male
- Organ Specificity
- Oxidopamine/toxicity
- Quinpirole
- Rats
- Rats, Wistar
- Receptors, Corticotropin
- Receptors, Pituitary Hormone/drug effects
- Receptors, Pituitary Hormone/physiology
- Sulpiride/pharmacology
- alpha-MSH/pharmacology
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Affiliation(s)
- W J Florijn
- Department of Pharmacology, Rudolf Magnus Institute, Medical Faculty, University of Utrecht, The Netherlands
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16
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de Barioglio SR, Lezcano NE, Celis ME. Independent and simultaneous effects of alpha-MSH and dopamine on cyclic AMP levels in rat brain slices. Ann N Y Acad Sci 1993; 680:594-6. [PMID: 8390199 DOI: 10.1111/j.1749-6632.1993.tb19748.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- S R de Barioglio
- Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
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17
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Hol EM, van Essen EH, Gispen WH, Bär PR. alpha-MSH and ACTH4-9 analogue Org 2766 induce a cAMP increase in cultured rat spinal cord cells. Ann N Y Acad Sci 1993; 680:533-5. [PMID: 8390185 DOI: 10.1111/j.1749-6632.1993.tb19730.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- E M Hol
- Department of Neurology, Utrecht University, Utrecht, The Netherlands
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18
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Charpentier N, Prézeau L, Carrette J, Bertorelli R, Le Cam G, Manzoni O, Bockaert J, Homburger V. Transfected Go1 alpha inhibits the calcium dependence of beta-adrenergic stimulated cAMP accumulation in C6 glioma cells. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(18)52968-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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19
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Lezcano NE, de Barioglio SR, de Vélez BM, Celis ME. Independent and simultaneous effects of alpha-MSH and dopamine on cyclic AMP levels in rat brain slices. Peptides 1993; 14:53-7. [PMID: 8382813 DOI: 10.1016/0196-9781(93)90010-e] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
This study was carried out to explore whether the postulated interaction between alpha-MSH and dopamine (DA) could be explained on the basis of variations in tissular cyclic AMP (cAMP) levels. We used slices containing caudate putamen and accumbens nuclei incubated in the presence of alpha-MSH, DA, or both simultaneously. Exposure of slices to alpha-MSH or DA resulted in an increase in cAMP levels. The simultaneous presence of alpha-MSH and DA resulted in a reduction in the accumulation of the cyclic nucleotide in the tissues as compared with those treated only with DA or alpha-MSH. The effect of alpha-MSH and DA on cAMP efflux was also tested. Incubation of slices with DA led to a marked increase in cAMP efflux; this efflux could be prevented if alpha-MSH was present in the medium. The results suggest that the inhibition by alpha-MSH of DA-induced striatal cAMP accumulation and efflux are a consequence of an interaction between the peptide and the neurotransmitter; DA and alpha-MSH transducing mechanisms could be biochemically linked.
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Affiliation(s)
- N E Lezcano
- Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
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20
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Tatro JB. Melanotropin Receptors of the Brain. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/b978-0-12-185271-9.50010-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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21
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Anglard P, Magal E, Louis JC. Stimulation of glycolysis by corticotropin and phorbol ester in cultured neurons. BIOCHIMICA ET BIOPHYSICA ACTA 1992; 1133:321-8. [PMID: 1531303 DOI: 10.1016/0167-4889(92)90054-f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Incubation of cultured neurons from chick embryo forebrain with corticotropin (ACTH) or the phorbol ester TPA (12-O-tetradecanoylphorbol 13-acetate) stimulates the production of lactate. The stimulation is seen after 2 h of treatment and is maximal after 12 h. Both ACTH (1-24) and TPA increase the concentration of fructose 2,6-bisphosphate (Fru-2,6-P2), a metabolic activator of 6-phosphofructo-1-kinase (PFK-1). This effect is concentration-dependent and is maximal after 4 h of treatment. PFK-1 activity is increased in a dose-dependent manner by ACTH (1-24) or TPA. This increase is not visible during the first 6 h and reaches its maximum after 18 h of treatment. The stimulation of PFK-1 activity is not due the increase of Fru-2,6-P2 by ACTH (1-24) or TPA, since saturating concentrations of Fru-2,6-P2 are present in the PFK-1 assay medium. Thus, it appears that ACTH (1-24) and TPA regulate glycolysis through two modes with different time responses: increase in Fru-2,6-P2 is the main mechanism operating during the first 6 h following the treatments and increase in the amount, or stable increase in activity of PFK-1, takes place during the later phase. It is suggested that the action of corticotropin on glycolysis is part of the mechanism of the neurotrophic activity of this hormone.
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Affiliation(s)
- P Anglard
- Centre de Neurochimie du CNRS, Strasbourg, France
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22
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Didier M, Roux P, Piechaczyk M, Mangeat P, Devilliers G, Bockaert J, Pin JP. Long-term expression of the c-fos protein during the in vitro differentiation of cerebellar granule cells induced by potassium or NMDA. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1992; 12:249-58. [PMID: 1312204 DOI: 10.1016/0169-328x(92)90091-o] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Levels of the c-fos protein were assayed in mouse cerebellar granule cells during their in vitro development under different culture conditions. When grown in media favoring both their survival and differentiation, i.e. in the presence of 30 mM K+ or 12.5 mM K+ plus 100 microM N-methyl-D-aspartate (NMDA), the c-fos protein becomes detectable in the nucleus of granule cells on and after 6 days and persists to high levels until the culture begins to decline. The protein c-fos appears therefore after the critical period described for the survival effect of K+ depolarization or NMDA receptor stimulation which corresponds to days 2-5 after plating. The c-fos protein remains however scarcely detectable or undetectable throughout the life-span of cells cultured under conditions providing poor survival and differentiation, i.e. in the presence of low K+ (5 or 12.5 mM) alone or when the effect of NMDA is blocked by the NMDA receptor antagonist MK-801. Interestingly, in cortical and striatal neurons, the survival and differentiation of which being not affected by depolarizing media, no c-fos protein is detected whatever the culture conditions tested at least during the first 18 days in vitro. This suggests that long-term expression of the c-fos gene might be related to some aspect of the late in vitro differentiation process of cerebellar granule cells.
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Affiliation(s)
- M Didier
- SANOFI recherche, Ligne de Neuropsychiatrie, Montpellier, France
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23
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Gallo-Payet N, Chouinard L, Balestre MN, Guillon G. Mechanisms involved in the interaction of dopamine with angiotensin II on aldosterone secretion in isolated and cultured rat adrenal glomerulosa cells. Mol Cell Endocrinol 1991; 81:11-23. [PMID: 1839152 DOI: 10.1016/0303-7207(91)90200-c] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In a previous study, we have shown that freshly isolated glomerulosa cells possess dopamine (DA) receptors from both DA-1 and DA-2 subclasses, whereas in cultured conditions, cells exhibit dopamine receptors from the DA-1 subclass only. In the present work, we have studied the effect of DA on angiotensin-stimulated glomerulosa cells in these two experimental conditions. Our results demonstrate that in isolated cells, angiotensin II (AT) stimulates inositol phosphate accumulation, calcium influx and steroid secretion. Treatment with pertussis toxin completely blocks AT-stimulated steroid secretion and calcium influx and partially reduces inositol phosphate accumulation. DA alone has no effect on cAMP accumulation. However, in the presence of a specific DA-1 antagonist (SCH 23390), DA reduces intracellular cAMP content. Similarly, DA-like pertussis toxin produces the same inhibitory effects on AT-stimulated cells. The combined influence of DA and pertussis toxin is not additive suggesting that a 'Gi' GTP-binding protein is involved in the DA action. Specific DA antagonists indicate that these inhibitory processes are mediated through the DA-2 receptor subtype. DA may act by decreasing the intracellular calcium concentration since it reduces AT-stimulated Ca2+ influx and that both phospholipase C (PLC) and steroid accumulation are calcium dependent. Yet a direct inhibitory coupling between the DA-2 receptor and PLC may represent a second alternative since DA inhibitory effects are always present when calcium influx is artificially increased or decreased. In cultured cells, we observe an additive effect of DA and AT on aldosterone secretion, which is the result of additive interactions of the second messengers involved, namely cAMP for dopamine and inositol phosphates for angiotensin II. From these studies, we conclude that DA may exert a more versatile effect on aldosterone secretion than previously suspected.
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Affiliation(s)
- N Gallo-Payet
- Department of Medicine, Faculty of Medicine, University of Sherbrooke, Quebec, Canada
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24
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Haynes L. Beta-endorphin C-terminal peptide evokes arachidonic acid release from cortical neurones. Eur J Pharmacol 1991; 192:397-401. [PMID: 1905234 DOI: 10.1016/0014-2999(91)90231-e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The release of free [3H]arachidonic acid and its metabolites (AAM) from mouse embryo cortical neurones cultured in serum-free medium stimulated by beta-endorphin C-terminal dipeptide (glycl-L-glutamine, Gly-Gln) was investigated. Gly-Gln but not the related dipeptide, glycyl-glutamic acid, caused a 2-fold elevation of AAM release which was blocked in the absence of extracellular calcium, in the presence of 5 mM magnesium and by the phospholipase A2 (PLA2) inhibitor, mepacrine. Other proopiomelanocortin (POMC) peptides did not elicit AAM release. The response to Gly-Gln was unaffected by D-amino-2-phospho-5-valeric acid (AP5) and 7-chlorokynurenic acid (7-ClKY), antagonists respectively at the ligand and allosteric glycine binding sites of the NMDA glutamate receptor subtype. However, it was inhibited in a dose-dependent manner by antagonists at the phencyclidine (PCP) and sigma sites. The results suggest that Gly-Gln causes AAM release by activating PLA2 through the mediation of a PCP/sigma-like receptor.
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Affiliation(s)
- L Haynes
- Department of Zoology, University of Bristol, U.K
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25
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Gallo-Payet N, Chouinard L, Balestre MN, Guillon G. Dual effects of dopamine in rat adrenal glomerulosa cells. Biochem Biophys Res Commun 1990; 172:1100-8. [PMID: 2173914 DOI: 10.1016/0006-291x(90)91560-f] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The effects of dopamine (DA) on cAMP production and aldosterone secretion were compared in freshly isolated cells and in primary cultures of rat adrenal glomerulosa cells. Under isolated conditions, glomerulosa cells exhibited dopamine receptors from DA-1 and DA-2 subclass, whereas in cultured conditions, where cells are very sensitive to their known stimuli, cells only exhibited dopamine receptors from the DA-1 subclass. Moreover, unlike freshly isolated cells, dopamine stimulated both cAMP production and aldosterone secretion in 3-day cultured preparations. These effects were receptor specific since they were completely suppressed by Scherring 23390 (a specific DA-1 antagonist) and were unaffected by a beta-adrenergic antagonist. As in vivo rat adrenal cortex contains DA, we discuss a possible involvement of this neurotransmitter in the regulation of aldosterone secretion.
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Affiliation(s)
- N Gallo-Payet
- Department of Medicine, Faculty of Medicine, University of Sherbrooke, Quebec, Canada
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26
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Agulló L, Picatoste F, García A. Histamine stimulation of cyclic AMP accumulation in astrocyte-enriched and neuronal primary cultures from rat brain. J Neurochem 1990; 55:1592-8. [PMID: 2170580 DOI: 10.1111/j.1471-4159.1990.tb04943.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Histamine stimulates cyclic AMP accumulation in astrocyte-enriched and neuronal primary cultures from rat brain in the presence of the phosphodiesterase inhibitor isobutylmethylxanthine. The response in the astrocyte cultures (Emax = 304 +/- 44% over basal, EC50 = 43 +/- 5 microM) was much higher than in neuronal cultures (Emax = 24 +/- 2%, EC50 = 14 +/- 7 microM). The histamine effect in astrocytes was competitively inhibited by the H2 antagonists cimetidine (Ki = 1.1 +/- 0.2 microM) and ranitidine (Ki = 46 +/- 10 nM) but was insensitive to the H1 antagonist mepyramine (1 microM). The two selective H2 agonists impromidine and dimaprit behaved as partial agonists and showed relative potencies (139 and 0.5, respectively) consistent with an interaction with H2 receptors. The more selective H1 agonist 2-thiazolylethylamine (0.01-1 mM) did not potentiate the response to impromidine (10 microM). Thus, in contrast to what is generally observed in intact cell preparations from brain, the histamine-induced cyclic AMP accumulation in astroglial cells is mediated solely by H2 receptors. The small effect shown in neuronal cultures also appears to be mediated by H2 receptors.
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Affiliation(s)
- L Agulló
- Instituto de Biología Fundamental V. Villar Palasi, Universidad Autónoma de Barcelona, Spain
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27
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Guillon G, Balestre MN, Lombard C, Rassendren F, Kirk CJ. Influence of bacterial toxins and forskolin upon vasopressin-induced inositol phosphate accumulation in WRK 1 cells. Biochem J 1989; 260:665-72. [PMID: 2548484 PMCID: PMC1138729 DOI: 10.1042/bj2600665] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The accumulation of inositol phosphates in WRK 1 cells, stimulated with a range of vasopressin concentrations, was diminished by prior exposure to cholera toxin or forskolin, whilst that observed in the presence of maximal concentrations of the hormone was enhanced in pertussis-toxin-treated cells. In the presence of [32P]NAD+, both cholera toxin and pertussis toxin provoked the labelling of peptides with approximate Mrs of 45,000 and 41,000 respectively in the membranes of WRK 1 cells. Exposure to cholera toxin or forskolin for 15-18 h enhanced cyclic AMP accumulation in these cells. The concentrations of these agents which provoked half-maximal cyclic AMP accumulation were similar to those required to diminish receptor-mediated inositol phosphate accumulation by 50%. In contrast, half-maximal ADP-ribosylation of the 45,000Mr peptide needed 100-fold greater concentrations of the toxin than were effective in provoking half-maximal inhibition of inositol phosphate accumulation. Cholera toxin or forskolin also reduced the maximal specific binding, to intact WRK 1 cells, of both [3H][Arg8]vasopressin and the V1a antagonist [3H][beta-mercapto-beta,beta-cyclopentamethylenepropionic acid,O-methyl-Tyr2, Arg8]vasopressin. The kinetics for the loss of this binding capacity following cholera-toxin treatment were very similar to those describing the diminution of vasopressin-stimulated inositol phosphate accumulation in the same cells.
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Affiliation(s)
- G Guillon
- Centre CNRS-INSERM de Pharmacologie-Endocrinologie, Montpellier, France
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28
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Berry S, Haynes LW. The opiomelanocortin peptide family: neuronal expression and modulation of neural cellular development and regeneration in the central nervous system. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. A, COMPARATIVE PHYSIOLOGY 1989; 93:267-72. [PMID: 2568228 DOI: 10.1016/0300-9629(89)90215-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
1. Pro-OMLC is amongst a small number of propeptide-encoding genes which are expressed at highest levels in the CNS early in development. 2. The reappearance of the peptide products in injured neurones suggests that they fulfill a function in neuronal growth, differentiation and regeneration. 3. Axonal cues may regulate gene expression in neurones with greater or less functional interaction with their target cells. 4. alpha-MSH and ACTH stimulate the differentiation of neurones by accelerating their energy uptake and axonal growth during its early phases. 5. Their neurotrophic action is mediated through a common N-terminal amino acid sequence. 6. The structure activity requirements of the molecular second messenger responses underlying this action have yet to be conclusively determined. 7. Endorphins may regulate the transition from the mitotic cycle to the onset of differentiation of neurones and glia in the CNS. 8. Little is yet known of the cellular mechanism underlying this response, but the control of peptide processing to favour opiate and non-opiate receptor-mediated responses may be a key factor in determining whether they accelerate or retard neuronal differentiation.
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Affiliation(s)
- S Berry
- Department of Zoology, University of Bristol, UK
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29
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Yasuda T, Sobue G, Mitsuma T, Takahashi A. Peptidergic and adrenergic regulation of the intracellular 3',5'-cyclic adenosine monophosphate content in cultured rat Schwann cells. J Neurol Sci 1988; 88:315-25. [PMID: 2852216 DOI: 10.1016/0022-510x(88)90228-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We investigated the role of neuropeptides and adrenergic agonists in the regulation of intracellular 3',5'-cyclic adenosine monophosphate (cyclic AMP) contents in cultured Schwann cells from sciatic nerve of neonatal Sprague-Dawley rats. Of the neuropeptides examined, vasoactive intestinal polypeptide (VIP) and secretin markedly stimulated the accumulation of intracellular cyclic AMP in a time- and dose-dependent manner with half maximum at 3 and 12 min, and 2.8 X 10(-5) and 5.0 X 10(-5) M, respectively. While somatostatin, substance P, adrenocorticotropin (ACTH), beta-endorphin, and nerve growth factor (NGF) did not show any effect on cyclic AMP metabolism, isoproterenol (IP), norepinephrine (NE) and epinephrine (E) also markedly elevated the Schwann cell cyclic AMP concentration. The rank-order of potency of these adrenergic catecholamines on cyclic AMP accumulation was isoproterenol greater than norepinephrine greater than epinephrine. Simultaneous addition of VIP or secretin to the Schwann cell culture synergistically enhanced the norepinephrine-induced elevation of intracellular cyclic AMP. The effect of norepinephrine was antagonized by a selective beta 1-adrenergic antagonist but not by beta 2- nor alpha-adrenergic antagonists. These results suggest that VIP, secretin, and beta 1-adrenergic agonists alone or synergistically may play a part in the regulation of metabolism of Schwann cells mediated through a cyclic AMP-dependent mechanism.
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Affiliation(s)
- T Yasuda
- Department of Neurology, Nagoya University School of Medicine, Japan
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30
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Guillon G, Gallo-Payet N, Balestre MN, Lombard C. Cholera-toxin and corticotropin modulation of inositol phosphate accumulation induced by vasopressin and angiotensin II in rat glomerulosa cells. Biochem J 1988; 253:765-75. [PMID: 2845933 PMCID: PMC1149369 DOI: 10.1042/bj2530765] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Vasopressin (VP) and angiotensin II (AT II) stimulate the production of inositol phosphates (IP) in rat glomerulosa cells. Guanosine 5'-[gamma-thio]triphosphate (GTP[S]), but not VP or AT II, stimulates IP production in a myo-[3H]inositol-prelabelled glomerulosa-cell membrane preparation. In combination with GTP[S], these hormones potentiate the response to GTP[S], indicating the existence of a G-protein involved in the coupling of the VP and AT II receptor with the phospholipase C. ADP-ribosylation with pertussis toxin (IAP) revealed the specific labelling of a single molecule of 41 kDa. No significant inhibition of VP- or AT II-stimulated IP accumulation was detected in intact cells when the whole 41 kDa molecule was endogenously ADP-ribosylated by IAP treatment. On the contrary, when glomerulosa cells were infected with cholera toxin (CT), both the VP- and AT II-stimulated IP accumulations were inhibited in a dose-dependent manner. Yet these effects were partial even at high concentrations of CT, and could not be related to the ADP-ribosylation of 'alpha s' molecules. Similarly, when the cells were infected with 1 microgram of CT/ml, the specific binding of VP and AT II decreased by 50-60%. Such results may signify that the treatment primarily affects the densities of the hormone receptors. When glomerulosa cells were incubated for 15 h in the presence of 10 nM-corticotropin (ACTH), a condition in which the intracellular concentration of cyclic AMP was increased 3-fold, the maximum IP response to 0.1 microM-VP or -AT II was decreased by 50%. When similar experiments were carried out only after a 15 min incubation period with the same concentration of ACTH, the increase in cyclic AMP was more pronounced, but no inhibition of hormone-induced IP accumulation was observed. Altogether, these results may suggest that CT exerts its action on the VP- or AT II-sensitive phospholipase C systems via a prolonged increase in intracellular cyclic AMP.
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Affiliation(s)
- G Guillon
- Centre CNRS-INSERM de Pharmacologie-Endocrinologie, Montpellier, France
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31
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Lockerbie RO, Hervé D, Blanc G, Tassin JP, Glowinski J. Isolated neuronal growth cones from developing rat forebrain possess adenylate cyclase activity which can be augmented by various receptor agonists. Brain Res 1988; 466:19-25. [PMID: 2829998 DOI: 10.1016/0165-3806(88)90082-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Isolated neuronal growth cones from neonatal rat forebrain were found to contain a high specific activity of adenylate cyclase (61 pmol cyclic AMP/min/mg protein) compared to the pelleted starting homogenate (5 pmol cyclic AMP/min/mg protein). Forskolin at 10(-4) M increased adenylate cyclase activity in both the pelleted homogenate and growth cone fraction by 70 and 217 pmol cyclic AMP/min/mg protein, respectively, over basal levels. The incremental effect of forskolin was 3-fold greater in the growth cone fraction than in the pelleted homogenate. However, relative to basal levels in each of the two fractions, forskolin increased adenylate cyclase activity in the growth cone fraction by only approx. 5-fold compared to 15-fold in the pelleted homogenate. Dopamine (10(-4) M), vasoactive intestinal polypeptide (10(-6) M) and isoproterenol (10(-5) M) also augmented adenylate cyclase activity in the two fractions. In the growth cone fraction, dopamine and vasoactive intestinal polypeptide produced a stimulation over basal levels by approx. 20 pmol cyclic AMP/min/mg protein while isoproterenol produced a stimulation of approx. 10 pmol cAMP/min/mg protein. The incremental effects of these receptor agonists in the growth cone fraction are approx. 5-fold greater than in the pelleted homogenate. The dopamine-sensitive adenylate cyclase activity in the growth cone fraction could be blocked by the compound SCH23390, a selective D1 receptor antagonist. At saturating concentrations, all combinations of dopamine, vasoactive intestinal polypeptide and isoproterenol were found to be completely additive on adenylate cyclase activity in the growth cone fraction.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- R O Lockerbie
- College de France, I.N.S.E.R.M. U. 114, Paris, France
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32
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Affiliation(s)
- A Dekker
- Division of Molecular Neurobiology, Rudolf Magnus Institute for Pharmacology, Utrecht, The Netherlands
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Weiss S, Kemp DE, Lenox RH, Ellis J. Alpha 2-adrenergic receptors mediate inhibition of cyclic AMP production in neurons in primary culture. Brain Res 1987; 414:390-4. [PMID: 3040169 DOI: 10.1016/0006-8993(87)90022-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The actions of adrenergic agents on the intracellular production of cyclic adenosine monophosphate (AMP) was examined in intact cortical and striatal neurons in primary culture, generated from the fetal mouse brain. Exposure of striatal neurons to the beta-adrenergic agonist isoproterenol (10 microM) resulted in a 5-fold increase in intraneuronal cyclic AMP; norepinephrine (100 microM), alone or in combination with isoproterenol, produced only a 3-fold increase in cyclic AMP levels. However, in the presence of yohimbine (10 microM), cyclic AMP productions due to norepinephrine or isoproterenol plus norepinephrine were identical to isoproterenol alone. When striatal or cortical neurons were exposed to pertussis toxin (100 ng/ml) overnight, there was no detectable difference between isoproterenol- and norepinephrine-stimulated cyclic AMP production. These data suggest that alpha 2-adrenergic receptors mediate the attenuation of cyclic AMP production in neurons and do so via the inhibitory guanine nucleotide regulatory protein of adenylate cyclase.
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Guillon G, Kirk CJ, Balestre MN. Characterization of specific V1a vasopressin-binding sites on a rat mammary-tumour-cell line. Biochem J 1986; 240:189-96. [PMID: 3030277 PMCID: PMC1147392 DOI: 10.1042/bj2400189] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
WRK 1, a cloned cell line derived from a rat mammary tumour, carries specific vasopressin-binding sites. Specific binding of 2-tyrosine-3H-labelled [8-lysine]vasopressin ([3H]vasopressin) was time-dependent, saturable and reversible. Scatchard-plot analysis of hormone binding indicated the presence of a single class of receptors with an equilibrium dissociation constant of 12.7 +/- 0.2 nM. The maximal binding capacity was 75 +/- 6 fmol/10(6) cells, which corresponds to approx. 45,000 sites per cell. Oxytocin and a highly potent oxytocin analogue were able to inhibit completely [3H]vasopressin binding, but, in this respect, they were far less potent than vasopressin. This clearly demonstrates the vasopressinergic nature of this receptor. Pharmacological studies using a series of 14 vasopressin or oxytocin analogues indicated that the ligand selectivity of the vasopressin receptor found on WRK 1 cells resembles that of the rat hepatocyte. This signifies that this vasopressin receptor is of the V1a subtype. This conclusion was confirmed by the observation that vasopressin did not influence the production of intracellular cyclic AMP in WRK 1 cells.
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Weiss S, Pin JP, Sebben M, Kemp DE, Sladeczek F, Gabrion J, Bockaert J. Synaptogenesis of cultured striatal neurons in serum-free medium: a morphological and biochemical study. Proc Natl Acad Sci U S A 1986; 83:2238-42. [PMID: 3008155 PMCID: PMC323267 DOI: 10.1073/pnas.83.7.2238] [Citation(s) in RCA: 116] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Striatal neurons were cultured from the fetal mouse brain and maintained in serum-free medium for 14-21 days in vitro (DIV). Pretreatment of the culture dishes successively with a polycation followed by fetal calf serum resulted in rapid neuron attachment and neurite proliferation. After 9-10 DIV, electron microscope observations revealed the presence of vesicles in axon terminals forming mature synapses with axons and perikarya of adjacent neurons and in varicosities along extended axons. Synapsin I, a synaptic vesicle-specific protein, was present only in neuronal perikarya after 3 DIV, in perikarya and in varicosities along extended axons after 6 DIV, and in varicosities and contact points between axon terminals and adjacent axons or perikarya after 11-14 DIV. Neurotransmitter-stimulated intracellular formation of cAMP decreased markedly during neuronal differentiation. Inositol phosphate formation in response to neurotransmitters, however, increased significantly throughout the period of striatal neuronal development. K+ (56 mM) depolarization resulted in a 2-fold increase in endogenous gamma-aminobutyric acid (GABA) release from striatal neurons, 50% of which was Ca2+-dependent, between 3 and 11 DIV. Between 11 and 14 DIV, subsequent to synapse formation (as revealed by electron microscope observations), GABA release evoked by 56 mM K+ increased up to 5-fold, 75% of which was Ca2+-dependent. It appears that the complete differentiation of striatal neurons in serum-free medium may provide a suitable model for the study of the physiological and regulatory mechanisms involved in nerve cell development.
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Weiss S, Sebben M, Kemp DE, Bockaert J. Serotonin 5-HT1 receptors mediate inhibition of cyclic AMP production in neurons. Eur J Pharmacol 1986; 120:227-30. [PMID: 3005002 DOI: 10.1016/0014-2999(86)90544-3] [Citation(s) in RCA: 84] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In purified striatal and cortical neurons in primary culture, serotonin (5-HT) stimulated basal cyclic AMP production (EC50, 0.5 microM) 2.5- and 1.5-fold, respectively. The 5-HT1 selective agonists, RU 24969 and 8-hydroxy-2-(di-n-propylamino)tetralin (PAT), did not stimulate cyclic AMP production. However, 5-HT, RU 24969 and PAT inhibited VIP-stimulated cyclic AMP formation in a dose-dependent manner. The actions of selective agonists and antagonists at 5-HT receptors mediating attenuation of cyclic AMP production suggest that they may be of the 5-HT1 subtype.
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Weiss S, Sebben M, Kemp DE, Bockaert J. Vasoactive intestinal peptide actions on cyclic AMP levels in cultured striatal neurons. Peptides 1986; 7 Suppl 1:187-92. [PMID: 3018697 DOI: 10.1016/0196-9781(86)90184-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The actions of vasoactive intestinal peptide (VIP) on intracellular cyclic AMP, in primary cultures of striatal neurons, were examined. VIP stimulated cyclic AMP formation five-fold over basal levels in neurons after 6 days in vitro (DIV); half maximal activation (EC50) was obtained with 10 nM of the peptide. VIP stimulation was both more potent and effective than those due to adrenocorticotropin (ACTH), dopamine (DA) or serotonin (5-HT). VIP efficacy was augmented to 15-20-fold in the presence of 0.1 microM forskolin, which had virtually no effect on cyclic AMP production alone; VIP potency was unaffected. At saturating concentrations of VIP (0.1-1.0 microM), no other agonist can further activate cyclic AMP production. Under these conditions, the interaction with opiate, DA D2 and 5-HT1 receptors, whose activation results in the inhibition of cyclic AMP production, was shown. During the differentiation of striatal neurons, VIP stimulation of cyclic AMP over basal levels, in the presence of 0.1 microM forskolin, decreases progressively from 30-fold after 3 DIV to 11-fold after 10-13 DIV.
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Anglard P, Zwiller J, Vincendon G, Louis JC. Regulation of cyclic AMP and cyclic GMP levels by adrenocorticotropic hormone in cultured neurons. Biochem Biophys Res Commun 1985; 133:286-92. [PMID: 3000376 DOI: 10.1016/0006-291x(85)91873-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The effect of adrenocorticotropic hormone (ACTH) on the intracellular concentration of cyclic nucleotides was studied in cultures of neurons from embryonic chick cerebral hemispheres. Incubation of neurons with ACTH(1-24) in the presence of phosphodiesterase inhibitor isobutylmethylxanthine resulted in a sustained increase in cyclic AMP while rise in cyclic GMP level was transient. The values obtained for half-maximal stimulation were 0.5 microM and 0.03 nM for cyclic AMP and cyclic GMP respectively. Concomitantly, ACTH(1-24) stimulated guanylate cyclase activity (half-maximal stimulation at 0.02 nM). These results suggest the existence of two distinct populations of ACTH receptors in neurons and provide the first evidence that cyclic GMP does mediate the action of ACTH in neurons.
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