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Vistoropsky Y, Heiblum R, Smorodinsky NI, Barnea A. Active immunization against vasoactive intestinal polypeptide decreases neuronal recruitment and inhibits reproduction in zebra finches. J Comp Neurol 2016; 524:2516-28. [PMID: 26801210 DOI: 10.1002/cne.23971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 11/26/2015] [Accepted: 01/19/2016] [Indexed: 01/21/2023]
Abstract
Neurogenesis and neuronal recruitment occur in adult brains of many vertebrates, and the hypothesis is that these phenomena contribute to the brain plasticity that enables organisms to adjust to environmental changes. In mammals, vasoactive intestinal polypeptide (VIP) is known to have many neuroprotective properties, but in the avian brain, although widely distributed, its role in neuronal recruitment is not yet understood. In the present study we actively immunized adult zebra finches against VIP conjugated to KLH and compared neuronal recruitment in their brains, with brains of control birds, which were immunized against KLH. We looked at two forebrain regions: the nidopallium caudale (NC), which plays a role in vocal communication, and the hippocampus (HC), which is involved in the processing of spatial information. Our data demonstrate that active immunization against VIP reduces neuronal recruitment, inhibits reproduction, and induces molting, with no change in plasma prolactin levels. Thus, our observations suggest that VIP has a direct positive role in neuronal recruitment and reproduction in birds. J. Comp. Neurol. 524:2516-2528, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Yulia Vistoropsky
- Department of Natural and Life Sciences, The Open University of Israel, Ra'anana, 43107, Israel
| | - Rachel Heiblum
- Department of Natural and Life Sciences, The Open University of Israel, Ra'anana, 43107, Israel
| | - Nechama-Ina Smorodinsky
- Department of Cell Research & Immunology, The George Wise Faculty of Life Sciences, Tel-Aviv University, Tel-Aviv, 61391, Israel
| | - Anat Barnea
- Department of Natural and Life Sciences, The Open University of Israel, Ra'anana, 43107, Israel
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Streiter S, Fisch B, Sabbah B, Ao A, Abir R. The importance of neuronal growth factors in the ovary. Mol Hum Reprod 2015; 22:3-17. [DOI: 10.1093/molehr/gav057] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2014] [Accepted: 10/14/2015] [Indexed: 12/29/2022] Open
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4
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Rosas G, Ramírez MI, Linares R, Trujillo A, Domínguez R, Morales-Ledesma L. Asymmetric steroidogenic response by the ovaries to the vasoactive intestinal peptide. Endocrine 2015; 48:968-77. [PMID: 25331816 DOI: 10.1007/s12020-014-0449-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 10/07/2014] [Indexed: 12/01/2022]
Abstract
In vitro the vasoactive intestinal peptide (VIP) stimulates progesterone, androgens, and estradiol secretion, and the effects are time-dependent. The present study analyzed the acute (1 h) and sub-acute (24 h) effects of unilateral injection of VIP into the ovarian bursa on each day of the estrous cycle on progesterone, testosterone, and estradiol serum levels. Cyclic 60-day-old virgin female rats on diestrus-1, diestrus-2, proestrus, or estrus were injected with saline or VIP 10(-6) M into the left or right ovarian bursa. One hour after saline injection on each day of estrus cycle, progesterone levels were higher than in control animals. The acute effects of saline solution on testosterone and estradiol levels were asymmetric and varied during the estrous cycle. In comparison with saline groups, the effects of VIPergic stimulation on progesterone, testosterone, and estradiol serum levels depend on the time elapsed between treatment and autopsy and vary during the estrous cycle. An acute asymmetric response from the ovaries to the VIP was observed at diestrus-1, diestrus-2, and proestrus on progesterone and estradiol levels. The asymmetries on testosterone levels were observed at diestrus-1, diestrus-2, and estrus days. The present results suggest that in the cyclic rat, each ovary has different sensitivities to VIPergic stimulation which depends on the endocrine status of the animal.
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Affiliation(s)
- Gabriela Rosas
- Biology of Reproduction Research Unit, Physiology of Reproduction Laboratory, Facultad de Estudios Superiores Zaragoza, UNAM, AP 9-020, CP 15000, Mexico, D.F., Mexico
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5
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Kowalewski MP, Dyson MT, Boos A, Stocco DM. Vasoactive intestinal peptide (VIP)-mediated expression and function of steroidogenic acute regulatory protein (StAR) in granulosa cells. Mol Cell Endocrinol 2010; 328:93-103. [PMID: 20655982 PMCID: PMC5010784 DOI: 10.1016/j.mce.2010.07.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2010] [Revised: 07/14/2010] [Accepted: 07/16/2010] [Indexed: 10/19/2022]
Abstract
VIP is a peptide hormone capable of activating the cAMP/PKA pathway and modifying gonadal steroidogenic capacity. Less is known about the molecular mechanisms of VIP-mediated steroidogenesis and its role in regulating the steroidogenic acute regulatory protein (STAR). We examined the impact of VIP on STAR expression and function in immortalized (KK1) and primary mouse granulosa cells, where VIP strongly upregulated STAR expression and steroidogenesis. Inhibitors of the PKA and PKC pathways suggested that both are activated by VIP. VIP did not efficiently phosphorylate STAR (P-STAR); however, VIP together with cAMP-analogs that activate Type II PKA increased P-STAR and further increased steroidogenesis. Our results suggest that VIP-induced STAR expression and function in granulosa cells result from the preferential activation of Type I PKA. Furthermore, the PKA and PKC pathways appear to converge at regulating VIP-mediated Star transcription and translation.
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Affiliation(s)
- Mariusz P Kowalewski
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center, 3601 4th Street, Lubbock, TX 79430, United States
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6
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VIP, from gene to behavior and back: summarizing my 25 years of research. J Mol Neurosci 2008; 36:115-24. [PMID: 18607776 DOI: 10.1007/s12031-008-9105-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2008] [Accepted: 05/15/2008] [Indexed: 11/25/2022]
Abstract
Vasoactive intestinal peptide (VIP) is an interesting example of a 28-amino acid neuropeptide that is abundantly expressed in discrete brain regions/neurons and hence may contribute to brain function. This short review summarizes my own point of view and encompasses 25 years of work and over 100 publications targeting the understanding of VIP production and biological activity. The review starts with our original cloning of the VIP gene, it then continues to discoveries of regulation of VIP synthesis and the establishment of the first VIP transgenic mice. The review ends with the identification of novel VIP analogs that helped decipher VIP's important role during development, in regulation of the biological clock(s) and diurnal rhythms, sexual activity, learning and memory as well as social behavior, and cancer. This review cites only articles that I have coauthored and gives my own perspective of this exciting ever-growing field.
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Barberi M, Muciaccia B, Morelli MB, Stefanini M, Cecconi S, Canipari R. Expression localisation and functional activity of pituitary adenylate cyclase-activating polypeptide, vasoactive intestinal polypeptide and their receptors in mouse ovary. Reproduction 2007; 134:281-92. [PMID: 17660238 DOI: 10.1530/rep-07-0051] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal polypeptide (VIP) positively affect several parameters correlated with the ovulatory process. PACAP is transiently expressed in rat preovulatory follicles, while VIP is present in nerve fibres at all stages of development. These two peptides act by interacting with three types of receptors: PACAP type I receptor (PAC1-R), which binds with higher affinity to PACAP, and two VIP receptors (VPAC1-R and VPAC2-R), which bind to PACAP and VIP with equal affinity. The aim of the present study was to characterise the PACAP/VIP/receptor system in the mouse ovary. Results obtained by RT-PCR, immunohistochemistry and in situ hybridisation showed that PACAP was transiently expressed in granulosa cells of preovulatory follicles after human chorionic gonadotrophin (hCG) stimulation, while VIP mRNA was never observed. All the receptors were present in 22-day-old untreated mice. In preovulatory follicles, PAC1-R was expressed both in granulosa cells and in residual ovarian tissue but was stimulated by hCG mainly in granulosa cells; VPAC2-R was present in both the cell compartments and was only mildly stimulated; VPAC1-R was present mainly in the residual ovarian tissue and was downregulated by hCG. PACAP and VIP were equipotent in inhibiting apoptosis in granulosa cells, confirming the presence of functional PACAP/VIP receptors. The contemporary induction by hCG of PACAP and PAC1-R in granulosa cells of preovulatory follicles suggests that, also in mouse ovary, PACAP may play a significant role around the time of ovulation. Moreover, the presence of PACAP/VIP receptors in the untreated ovary suggests a possible role for PACAP and VIP during follicle development.
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MESH Headings
- Animals
- Chorionic Gonadotropin/pharmacology
- Female
- Gene Expression
- Granulosa Cells/chemistry
- Granulosa Cells/metabolism
- Immunohistochemistry
- In Situ Hybridization
- Mice
- Mice, Inbred Strains
- Ovary/chemistry
- Ovary/metabolism
- Pituitary Adenylate Cyclase-Activating Polypeptide/analysis
- Pituitary Adenylate Cyclase-Activating Polypeptide/genetics
- Pituitary Adenylate Cyclase-Activating Polypeptide/metabolism
- RNA, Messenger/analysis
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I/analysis
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I/genetics
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I/metabolism
- Receptors, Vasoactive Intestinal Peptide/analysis
- Receptors, Vasoactive Intestinal Peptide/genetics
- Receptors, Vasoactive Intestinal Peptide/metabolism
- Receptors, Vasoactive Intestinal Peptide, Type II/analysis
- Receptors, Vasoactive Intestinal Peptide, Type II/genetics
- Receptors, Vasoactive Intestinal Peptide, Type II/metabolism
- Receptors, Vasoactive Intestinal Polypeptide, Type I/analysis
- Receptors, Vasoactive Intestinal Polypeptide, Type I/genetics
- Receptors, Vasoactive Intestinal Polypeptide, Type I/metabolism
- Reverse Transcriptase Polymerase Chain Reaction
- Tissue Culture Techniques
- Vasoactive Intestinal Peptide/analysis
- Vasoactive Intestinal Peptide/genetics
- Vasoactive Intestinal Peptide/metabolism
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Affiliation(s)
- Marzia Barberi
- Department of Histology and Medical Embriology, La Sapienza University of Rome, Via A. Scarpa, 14, Rome 00161, Italy
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Parra C, Fiedler JL, Luna SL, Greiner M, Padmanabhan V, Lara HE. Participation of vasoactive intestinal polypeptide in ovarian steroids production during the rat estrous cycle and in the development of estradiol valerate-induced polycystic ovary. Reproduction 2007; 133:147-54. [PMID: 17244741 DOI: 10.1530/rep.1.01214] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Vasoactive intestinal polypeptide (VIP) stimulates estradiol and progesterone release from ovarian granulosa cellsin vitro. Very little information is available as to the role VIP plays in the control of steroid secretion during reproductive cyclicity and in ovarian pathologies involving altered steroid secretion. In this study, we determined the involvement of VIP in regulating ovarian androgen and estradiol release during estrous cyclicity and estradiol valerate (EV)-induced polycystic ovarian development in rats. Our findings show that androgen and estradiol release from ovaries obtained during different stages of rat estrous cycle mimic cyclic changes in steroid release observedin vivowith maximal release occurring during late proestrus. VIP increased androgen release from ovaries of all cycle stages except late proestrus and estradiol release from all cycle stages. Increases in VIP-induced androgen and estradiol release were maximal at early proestrus. Inclusion of saturating concentrations of androstenedione increased magnitude of VIP-induced estradiol release at diestrus and estrus but not proestrus. Magnitude of VIP-induced androgen and estradiol release tended to be greater in the ovaries from EV-treated rats with polycystic ovary compared with estrous controls. At the tissue level, ovarian VIP concentration was cycle stage dependent with highest level seen in diestrus. Maximum concentration of VIP was found in EV-treated rats. Changes in VIP were inversely related to changes in ovarian nerve growth factor, a neuropeptide involved in ovarian androgen secretion. These results strongly suggest that intraovarian VIP participates in the control of estradiol secretion during the rat estrous cycle and possibly in the maintenance of increased ovarian estradiol secretory activity of EV-treated rats.
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Affiliation(s)
- Claudio Parra
- Lab. Neurobioquímica, Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago, Chile
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9
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Conconi MT, Spinazzi R, Nussdorfer GG. Endogenous Ligands of PACAP/VIP Receptors in the Autocrine–Paracrine Regulation of the Adrenal Gland. INTERNATIONAL REVIEW OF CYTOLOGY 2006; 249:1-51. [PMID: 16697281 DOI: 10.1016/s0074-7696(06)49001-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) are the main endogenous ligands of a class of G protein-coupled receptors (Rs). Three subtypes of PACAP/VIP Rs have been identified and named PAC(1)-Rs, VPAC(1)-Rs, and VPAC(2)-Rs. The PAC(1)-R almost exclusively binds PACAP, while the other two subtypes bind with about equal efficiency VIP and PACAP. VIP, PACAP, and their receptors are widely distributed in the body tissues, including the adrenal gland. VIP and PACAP are synthesized in adrenomedullary chromaffin cells, and are released in the adrenal cortex and medulla by VIPergic and PACAPergic nerve fibers. PAC(1)-Rs are almost exclusively present in the adrenal medulla, while VPAC(1)-Rs and VPAC(2)-Rs are expressed in both the adrenal cortex and medulla. Evidence indicates that VIP and PACAP, acting via VPAC(1)-Rs and VPAC(2)-Rs coupled to adenylate cyclase (AC)- and phospholipase C (PLC)-dependent cascades, stimulate aldosterone secretion from zona glomerulosa (ZG) cells. There is also proof that they can also enhance aldosterone secretion indirectly, by eliciting the release from medullary chromaffin cells of catecholamines and adrenocorticotropic hormone (ACTH), which in turn may act on the cortical cells in a paracrine manner. The involvement of VIP and PACAP in the regulation of glucocorticoid secretion from inner adrenocortical cells is doubtful and surely of minor relevance. VIP and PACAP stimulate the synthesis and release of adrenomedullary catecholamines, and all three subtypes of PACAP/VIP Rs mediate this effect, PAC(1)-Rs being coupled to AC, VPAC(1)-Rs to both AC and PLC, and VPAC(2)-Rs only to PLC. A privotal role in the catecholamine secretagogue action of VIP and PACAP is played by Ca(2+). VIP and PACAP may also modulate the growth of the adrenal cortex and medulla. The concentrations attained by VIP and PACAP in the blood rule out the possibility that they act as true circulating hormones. Conversely, their adrenal content is consistent with a local autocrine-paracrine mechanism of action.
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Affiliation(s)
- Maria Teresa Conconi
- Department of Pharmaceutical Sciences, School of Pharmacy, University of Padua, I-35121 Padua, Italy
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10
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Romero C, Paredes A, Dissen GA, Ojeda SR. Nerve growth factor induces the expression of functional FSH receptors in newly formed follicles of the rat ovary. Endocrinology 2002; 143:1485-94. [PMID: 11897707 DOI: 10.1210/endo.143.4.8711] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The neurotrophin nerve growth factor (NGF) and its two membrane-anchored receptors are expressed in the developing ovary before the organization of the first primordial follicles. In the absence of NGF, the growth of primordial follicles is retarded, indicating that NGF contributes to facilitating early follicular development. The present experiments were undertaken to determine whether NGF can also be involved in the differentiation process by which ovarian follicles become responsive to gonadotropins. Treatment of 2-d-old rat ovaries in organ culture with NGF increased FSH receptor (FSHR) mRNA within 8 h of exposure. This effect was cAMP-independent but additive to the cAMP-mediated increase in FSHR gene expression induced by either forskolin or vasoactive intestinal peptide, a neurotransmitter previously shown to induce FSHR formation in neonatal rat ovaries. After NGF treatment, the ovary acquired the capacity of responding to FSH with cAMP formation and preantral follicular growth, indicating that exposure to the neurotrophin resulted in the formation of biologically active FSHRs. Quantitative measurement of FSHR mRNA demonstrated that the content of FSHR mRNA is reduced in the ovaries of mice carrying a null mutation of the NGF gene. These results indicate that one of the functions of NGF in the developing ovary is to facilitate the differentiation process by which early growing follicles become gonadotropin-dependent during postnatal life, and that it does so by increasing the synthesis of FSHRs.
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Affiliation(s)
- Carmen Romero
- Division of Neuroscience, Oregon Regional Primate Research Center/Oregon Health Science University, Beaverton, Oregon 97006, USA
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11
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Sherwood NM, Krueckl SL, McRory JE. The origin and function of the pituitary adenylate cyclase-activating polypeptide (PACAP)/glucagon superfamily. Endocr Rev 2000; 21:619-70. [PMID: 11133067 DOI: 10.1210/edrv.21.6.0414] [Citation(s) in RCA: 157] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The pituitary adenylate cyclase-activating polypeptide (PACAP)/ glucagon superfamily includes nine hormones in humans that are related by structure, distribution (especially the brain and gut), function (often by activation of cAMP), and receptors (a subset of seven-transmembrane receptors). The nine hormones include glucagon, glucagon-like peptide-1 (GLP-1), GLP-2, glucose-dependent insulinotropic polypeptide (GIP), GH-releasing hormone (GRF), peptide histidine-methionine (PHM), PACAP, secretin, and vasoactive intestinal polypeptide (VIP). The origin of the ancestral superfamily members is at least as old as the invertebrates; the most ancient and tightly conserved members are PACAP and glucagon. Evidence to date suggests the superfamily began with a gene or exon duplication and then continued to diverge with some gene duplications in vertebrates. The function of PACAP is considered in detail because it is newly (1989) discovered; it is tightly conserved (96% over 700 million years); and it is probably the ancestral molecule. The diverse functions of PACAP include regulation of proliferation, differentiation, and apoptosis in some cell populations. In addition, PACAP regulates metabolism and the cardiovascular, endocrine, and immune systems, although the physiological event(s) that coordinates PACAP responses remains to be identified.
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Affiliation(s)
- N M Sherwood
- Department of Biology, University of Victoria, British Columbia, Canada.
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12
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Gräs S, Hedetoft C, Pedersen SH, Fahrenkrug J. Pituitary adenylate cyclase-activating peptide stimulates acute progesterone production in rat granulosa/Lutein cells via two receptor subtypes. Biol Reprod 2000; 63:206-12. [PMID: 10859261 DOI: 10.1095/biolreprod63.1.206] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Pituitary adenylate cyclase-activating peptide (PACAP) is transiently expressed in ovarian granulosa/lutein cells from eCG/hCG-treated rats, and in vitro immunoneutralization of endogenously released PACAP inhibits acute progesterone secretion and subsequent luteinization in such cells. This suggests that PACAP mediates locally some of the effects of the LH surge, but the putative PACAP receptor(s) involved in such an auto or paracrine activity is presently unknown. Reverse-transcription polymerase chain reaction with specific primers to the three cloned PACAP-binding receptors called PAC(1), VPAC(1), and VPAC(2) demonstrated both PAC(1) and VPAC(2) mRNA in extracts from preovulatory follicular cells. Radioligand-binding assays revealed the presence of high-affinity binding sites with characteristics of these two receptors on the intact cells, and autoradiography demonstrated that the binding was restricted to a minor proportion of the follicular cells as well as the oocytes. Pituitary adenylate cyclase-activating peptide and vasoactive intestinal peptide (VIP) dose-dependently stimulated cAMP accumulation and acute progesterone accumulation. Forskolin and db-cAMP also stimulated acute progesterone accumulation, and the protein kinase A inhibitor H89 dose-dependently inhibited peptide induced acute progesterone accumulation, suggesting involvement of cAMP and the protein kinase A pathway in the process. In conclusion, two of the three PACAP binding receptors are present on preovulatory follicular cells and are involved in the effects of PACAP on acute progesterone production. The data provide further evidence to establish PACAP as an auto- or paracrine regulator of LH-induced acute progesterone production in rat preovulatory follicles.
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MESH Headings
- Animals
- Autoradiography
- Colforsin/pharmacology
- Cyclic AMP/metabolism
- Cyclic AMP-Dependent Protein Kinase Type II
- Cyclic AMP-Dependent Protein Kinases/drug effects
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Female
- Granulosa Cells/drug effects
- Granulosa Cells/metabolism
- Iodine Radioisotopes
- Lutein/metabolism
- Neuropeptides/metabolism
- Neuropeptides/pharmacology
- Pituitary Adenylate Cyclase-Activating Polypeptide
- Progesterone/metabolism
- Protein Isoforms/metabolism
- Rats
- Rats, Wistar
- Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide
- Receptors, Pituitary Hormone/drug effects
- Receptors, Pituitary Hormone/genetics
- Receptors, Pituitary Hormone/metabolism
- Receptors, Vasoactive Intestinal Peptide/genetics
- Receptors, Vasoactive Intestinal Peptide/metabolism
- Receptors, Vasoactive Intestinal Peptide, Type II
- Receptors, Vasoactive Intestinal Polypeptide, Type I
- Reverse Transcriptase Polymerase Chain Reaction
- Vasoactive Intestinal Peptide/pharmacology
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Affiliation(s)
- S Gräs
- Department of Clinical Biochemistry, University of Copenhagen, Bispebjerg Hospital, DK-2400 Copenhagen NV, Denmark
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Gozes I, Perl O, Zamostiano R, Rubinraut S, Fridkin M, Shochat L, Lewin LM. Multiple actions of a hybrid PACAP antagonist: neuronal cell killing and inhibition of sperm motility. Ann N Y Acad Sci 1998; 865:266-73. [PMID: 9928021 DOI: 10.1111/j.1749-6632.1998.tb11187.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Pituitary stimulating adenylate cyclase (PACAP) is a major regulatory peptide with two active molecular forms: PACAP-27 and PACAP-38. Both molecular forms promote neuronal survival and protect against neurotoxicity. Based on our previous hybrid peptide strategy in designing vasoactive intestinal peptide (VIP) antagonists, novel PACAP analogues were synthesized (neurotensin6-11 PACAP7-27 and neurotensin6-11 PACAP7-38). In addition to the hybrid modification, the methionine in position 17 was replaced by norleucine (Nle). Treatment of rat cerebral cortical cultures for five days with the putative PACAP antagonists (1 nM) resulted in a 35-45% reduction in neuronal cell counts as compared to controls. Neuronal cell death was already obtained at picomolar concentrations for the neurotensin6-11 PACAP7-27 antagonist with 70% death at 10(-8) M. Co-administration of the PACAP hybrid analogue with picomolar amounts of PACAP-27 or Nle17-PACAP-27 attenuated the reduction in neuronal cell counts. While the protective effects of both analogues exhibited a peak at 1 pM concentrations, the Nle-containing agonist displayed a broader range of active concentrations (10(-12)M-10(-9) M). The putative PACAP antagonist also inhibited sperm motility (golden hamster) in a dose-dependent manner as assessed in vitro. Complete inhibition was observed at 10 microM, suggesting a role for PACAP in sperm motility and sexual function. Thus, previous findings of a large number of PACAP and PACAP receptors in the nervous system and the reproductive system are now correlated with a function in neuronal survival and sperm motility. The structure-activity studies suggest that the methionine in position 17 and the first six amino acids are important in the determination of PACAP activity, knowledge that may facilitate PACAP-based drug design.
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Affiliation(s)
- I Gozes
- Department of Clinical Biochemistry, Sackler School of Medicine, Tel Aviv University, Israel.
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Apa R, Lanzone A, Mastrandrea M, Miceli F, de Feo D, Caruso A, Mancuso S. Control of human luteal steroidogenesis: role of growth hormone-releasing hormone, vasoactive intestinal peptide, and pituitary adenylate cyclase-activating peptide. Fertil Steril 1997; 68:1097-102. [PMID: 9418704 DOI: 10.1016/s0015-0282(97)00370-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To examine the possible effect of growth hormone-releasing hormone (GHRH), vasoactive intestinal peptide, and pituitary adenylate cyclase-activating peptide on basal and hCG-stimulated P production by human luteal cells. DESIGN Cultures of human luteal cells from the early and midluteal phase. SETTING All corpora lutea were obtained from the Obstetrics and Gynecology Department of the Università Cattolica, a public care center. PATIENT(S) Ten nonpregnant women between 35 and 47 years of age underwent surgery for various nonendocrine disorders, such as leiomyomatosis. INTERVENTION(S) Corpora lutea were obtained at the time of hysterectomy. MAIN OUTCOME MEASURE(S) Luteal cells were incubated with GHRH, vasoactive intestinal peptide, and pituitary adenylate cyclase-activating peptide with or without hCG at different concentrations. RESULT(S) Pituitary adenylate cyclase-activating peptide stimulated P production in a dose- and time-dependent manner, whereas GHRH and vasoactive intestinal peptide did not affect luteal steroidogenesis. None of the three peptides were found to synergize with hCG. CONCLUSION(S) Pituitary adenylate cyclase-activating peptide can influence human luteal steroidogenesis.
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Affiliation(s)
- R Apa
- Institute of Obstetrics and Gynecology, Università Cattolica del Sacro Cuore, Rome, Italy
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15
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Shioda S, Nakai Y, Nakajo S, Nakaya K, Arimura A. Localization of pituitary adenylate cyclase-activating polypeptide and its type I receptors in the rat ovary: immunohistochemistry and in situ hybridization. Ann N Y Acad Sci 1996; 805:677-83. [PMID: 8993460 DOI: 10.1111/j.1749-6632.1996.tb17540.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- S Shioda
- U.S.-Japan Biomedical Research Laboratories, Tulane University Hebert Center, Belle Chasse, Louisiana 70037, USA.
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16
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Ledda S, Bogliolo L, Leoni G, Calvia P, Naitana S. Influence of vasoactive intestinal peptide (VIP), atrial natriuretic peptide (ANP) and insulin-like growth factor-I (IGF-I) on in vitro maturation of prepubertal and adult sheep oocytes. ZYGOTE 1996; 4:343-8. [PMID: 9153777 DOI: 10.1017/s0967199400003361] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Much effort has been focused on establishing optimal conditions for obtainingin vitromaturation of oocytes from different species with results comparable to those achieved afterin vivodevelopment (reviewed by Brackett, 1992). However, even though extraordinary progress has been made, thein vitrotechnology for oocyte maturation lags far behind thatin vivoand improvements are needed to increase the quantity and quality of the embryos produced from these matured oocytes.
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Affiliation(s)
- S Ledda
- Dipartimento di Biologia Animale, Sassari, Italy
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17
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Ottesen B, Fahrenkrug J. Vasoactive intestinal polypeptide and other preprovasoactive intestinal polypeptide-derived peptides in the female and male genital tract: localization, biosynthesis, and functional and clinical significance. Am J Obstet Gynecol 1995; 172:1615-31. [PMID: 7755080 DOI: 10.1016/0002-9378(95)90506-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Vasoactive intestinal polypeptide, a neuropeptide with wide distribution in the central and peripheral nervous system, has a broad spectrum of biologic actions. The demonstration of vasoactive intestinal polypeptide containing nerve fibers within the female and male genital tract 17 years ago indicated a putative role for this peptide in the local nervous control of reproductive functions. The genes encoding the preprovasoactive intestinal polypeptide precursor molecule and the vasoactive intestinal polypeptide receptor have been identified. The gene expression has been studied by the use of specific antibodies against the functional domains of the vasoactive intestinal polypeptide precursor and the biologic action elucidated by both in vivo and in vitro methods. Evidence has been provided to support vasoactive intestinal polypeptide as a neurotransmitter in several physiologic events in the genital tracts (i.e., blood flow and nonvascular smooth muscle relaxation). In the ovary vasoactive intestinal polypeptide seems to play an important role as regulator and/or modulator of folliculogenesis and steroidogenesis. In the male genital tract vasoactive intestinal polypeptide seems to participate in the control of erection. Vasoactive intestinal polypeptide has been suggested as a causative factor in some diseases of the genital organs (e.g., it may play a pathophysiologic role in male impotence and the peptide is currently used in the treatment of this condition). Vasoactive intestinal polypeptide may be important for control of the low resistance in the fetomaternal vascular bed and is therefore a putative factor involved in the development of preeclampsia. The therapeutic potential of vasoactive intestinal polypeptide and future agonists and antagonists will be revealed by ongoing and forthcoming studies.
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Affiliation(s)
- B Ottesen
- Department of Obstetrics and Gynecology, Hvidovre Hospital, University of Copenhagen, Denmark
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18
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Karakji EG, Tsang BK. Growth hormone releasing factor and vasoactive intestinal peptide stimulate rat granulosa cell plasminogen activator activity in vitro during follicular development. Mol Cell Endocrinol 1995; 107:105-12. [PMID: 7796929 DOI: 10.1016/0303-7207(94)03431-r] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Growth hormone-releasing factor (GRF) and vasoactive intestinal peptide (VIP) are two structurally homologous peptides sharing common target cell receptor and known to enhance FSH-induced steroidogenesis of undifferentiated granulosa cell in vitro. Although VIP, has been reported to stimulate plasminogen activator (PA) activity in rat granulosa cells, our knowledge on the actions and interactions of these two peptides with FSH in the regulation of rat granulosa cell PA system during follicular development remains incomplete. Undifferentiated and differentiated rat granulosa cells from pre-antral (DES-treated rats) and antral (eCG-treated rats) follicles, respectively, were cultured in a chemically defined medium in the absence and presence of FSH (400 ng/ml), GRF (10(-8)-10(-5) M) and/or VIP (10(-9)-10(-5) M). Net secreted (PAs) and cell-associated (PAc) PA activities was measured by the fibrinolysis assay and characterized by the fibrin overlay method. Granulosa cell differentiative (progestin secretion) and proliferative (DNA synthesis) responses were analyzed by radioimmunoassay and [3H]thymidine incorporation, respectively. Both GRF and VIP stimulated PAs and PAc activities in a concentration-dependent manner in 24-h cultures of granulosa cells from the two stages of follicular development. They (10(-5) M) enhanced FSH-stimulated PAs activity in granulosa cell cultures of pre-antral follicles, with GRF being more effective than VIP. On the contrary, only GRF (10 microM) potentiated FSH-induced PAs and PAc activities in cultures of granulosa cell from antral follicles. The stimulation of PA activity by these agonists decreased with the duration of culture irrespective of the stage of follicular development.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- E G Karakji
- Department of Obstetrics and Gynaecology, University of Ottawa, Ontario, Canada
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19
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Liedberg F, Kannisto P, Owman C, Schmidt G. Effects of vasoactive intestinal polypeptide (VIP) on the neuromuscular complex in the bovine ovarian follicle wall. JOURNAL OF AUTONOMIC PHARMACOLOGY 1993; 13:201-9. [PMID: 8514821 DOI: 10.1111/j.1474-8673.1993.tb00267.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
1. When stimulating the local nerves in the bovine ovarian follicle wall preparation (4 Hz, 1 ms pulse duration and 7.5 V between the electrodes) vasoactive intestinal polypeptide reduced the neurogenic contraction and at the highest concentration tested (3 x 10(-7) M) almost abolished the response. Peptide histidine isoleucine only slightly reduced the contraction. 2. Strips from the follicle wall of bovine ovaries were incubated in Krebs-Ringer solution containing [3H]-noradrenaline for measurement of transmitter liberation during electrical field stimulation (5 Hz frequency, 1 ms pulse duration, 10 V between the electrodes). Vasoactive intestinal polypeptide had no effect on the electrically induced efflux of radioactivity. 3. Vasoactive intestinal polypeptide and its related peptide, peptide histidine isoleucine, relaxed precontracted follicle strips dose dependently with I(max) at 3 x 10(-7) M of 60% and 40% respectively. 4. Vasoactive intestinal polypeptide 10(-7) M did not alter the EC50 value of the noradrenaline-(10(-9)-10(-4) M) or carbachol-induced (10(-8)-3 x 10(-4) M) contraction in the follicle strips, but significantly reduced the E(max) value of the noradrenaline but not the carbochol-mediated contraction. 5. These results suggests that vasoactive intestinal polypeptide, and to some extent peptide histidine isoleucine, have a postjunctional role in ovarian follicle contractility and might further interfere with the ovulatory process.
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Affiliation(s)
- F Liedberg
- Department of Medical Cell Research, Lund, Sweden
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20
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Malamed S, Gibney JA, Ojeda SR. Ovarian innervation develops before initiation of folliculogenesis in the rat. Cell Tissue Res 1992; 270:87-93. [PMID: 1358455 DOI: 10.1007/bf00381883] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Sympathetic neurotransmitters have been shown to be present in the ovary of the rat during early postnatal development and to affect steroidogenesis before the ovary becomes responsive to gonadotropins, and before the first primordial follicles are formed. This study was undertaken to determine if development of the ovarian innervation is an event that antedates the initiation of folliculogenesis in the rat, Rattus norvegicus. Serial sections of postnatal ovaries revealed a negligible frequency of follicles 24 h after birth (about 1 primordial follicle per ovary). Twelve hours later there were about 500 follicles per ovary, a number that more than doubled to about 1300 during the subsequent 12 h, indicating that an explosive period of follicular differentiation occurs between the end of postnatal days 1 and 2. Electron microscopy demonstrated that before birth the ovaries are already innervated by fibers containing clear and dense-core vesicles. Immunohistochemistry performed on either fetal (day 19) or newborn (less than 15h after birth) ovaries showed the presence of catecholaminergic nerves, identified by their content of immunoreactive tyrosine hydroxylase (TH), the rate-limiting enzyme in catecholamine biosynthesis. While some of these fibers innervate blood vessels, others are associated with primordial ovarian cells, thereby suggesting their participation in non-vascular functions. Since prefollicular ovaries are insensitive to gonadotropins, the results suggest that the developing ovary becomes subjected to direct neurogenic influences before it acquires responsiveness to gonadotropins.
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Affiliation(s)
- S Malamed
- Department of Neuroscience and Cell Biology, UMDNJ-Robert Wood Johnson Medical School, Piscataway 08854
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21
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Spicer LJ, Langhout DJ, Alpizar E, Williams SK, Campbell RM, Mowles TF, Enright WJ. Effects of growth hormone-releasing factor and vasoactive intestinal peptide on proliferation and steroidogenesis of bovine granulosa cells. Mol Cell Endocrinol 1992; 83:73-8. [PMID: 1551471 DOI: 10.1016/0303-7207(92)90197-e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Recent studies have suggested that growth hormone-releasing factor (GRF), like vasoactive intestinal peptide (VIP), may enhance follicle-stimulating hormone (FSH)-stimulated steroidogenesis in cultured rat granulosa cells (GC). Because effects of GRF or VIP on GC proliferation have not been reported, we evaluated and compared the effect of GRF to that of VIP using cultured bovine GC. Undifferentiated GC from 1-5 mm bovine follicles were established for 2 days in medium containing 10% fetal calf serum, washed and then cultured in chemically defined medium for an additional 2 days. Two-day treatment with 2.5-1000 ng/ml of VIP had no effect (P greater than 0.05) on proliferation or progesterone production of bovine GC in the presence or absence of 200 ng/ml FSH. In comparison, 100, 250, 500, 1000 or 2000 pg/ml of human [desNH2Tyr1,D-Ala2,Ala15]-GRF(1-29)-NH2 analog caused a dose-dependent stimulation (P less than 0.05) of GC proliferation in the absence and presence of 5 micrograms/ml insulin. However, the GRF analog had no effect (P greater than 0.05) on GC progesterone production (expressed as ng/10(5) cells/24 h) in the absence or presence of 5 micrograms/ml insulin. The effects of GRF analog on progesterone production and cell proliferation were not influenced by co-culture with 200 ng/ml FSH. GRF(1-44)-NH2 also stimulated cell proliferation but had no effect on basal or FSH-induced progesterone production. These results suggest that GRF may play a role in GC proliferation during follicular development in the bovine.
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Affiliation(s)
- L J Spicer
- Department of Animal Science, Oklahoma State University, Stillwater 74078
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22
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Lamperti ED, Rosen KM, Villa-Komaroff L. Characterization of the gene and messages for vasoactive intestinal polypeptide (VIP) in rat and mouse. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1991; 9:217-31. [PMID: 1851524 DOI: 10.1016/0169-328x(91)90005-i] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We have studied the structure and expression of the gene for vasoactive intestinal polypeptide (VIP) in rodents. We used a human cDNA to identify and clone a fragment of the rat VIP gene. This genomic fragment contained two separate exons, one encoding VIP itself and the other encoding a closely related neuropeptide, peptide histidine-isoleucine (PHI-27). Probes containing either exon, or both, hybridized to two messages: a prominent 1700-base (b) mRNA and a rare 1000-b species. These messages are expressed together in a tissue-specific manner, with highest levels in polyadenylated RNA from cerebral cortex and from small intestine, paralleling the reported levels of the neuropeptides themselves in these tissues. Using the rat genomic fragment as a probe, we isolated the mouse VIP gene in its entirety. The mouse gene is similar in organization to its human counterpart, with a total of 7 exons spanning 8 kilobases (kb). The 7th and largest exon, which is transcribed into the bulk of the 3' untranslated region of the messages, bears two potential polyadenylation sites 700 basepairs (bp) apart. S-1 nuclease protection with a fragment of this exon indicated that the two identifiable VIP messages differ in the extent of their 3' untranslated regions. Conversely, we found no evidence for differential splicing to produce messages encoding only one of the neuropeptides. Instead, specific oligonucleotide-directed digestion with RNase H demonstrated that all of the detectable mRNA from this gene contains both VIP and PHI coding sequences.
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Affiliation(s)
- E D Lamperti
- Department of Neurology, Children's Hospital, Boston, MA 02115
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23
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Abstract
In the mammalian brain, a major regulatory peptide is vasoactive intestinal peptide (VIP). This 28 amino acid peptide, originally isolated from the porcine duodenum, was later found in the central and peripheral nervous systems and in endocrine cells, where it exhibits neurotransmitter and hormonal roles. Increasing evidence points to VIP's importance as a mediator or a modulator of several basic functions. Thus, VIP is a major factor in brain activity, neuroendocrine functions, cardiac activity, respiration, digestion, and sexual potency. In view of this peptide's importance, the mechanisms controlling its production and the pathways regulating its functions have been reviewed. VIP is a member of a peptide family, including peptides such as glucagon, secretin, and growth hormone releasing hormone. These peptides may have evolved by exon duplication coupled with gene duplication. The human VIP gene contains seven exons, each encoding a distinct functional domain on the protein precursor or the mRNA. VIP gene transcripts are mainly found in neurons or neuron-related cells. VIP gene expression is regulated by neuronal and endocrine signals that contribute to its developmental control. VIP exerts its function via receptor-mediated systems, activating signal transduction pathways, including cAMP. It can act as a neurotransmitter, neuromodulator, and a secretagog. As a growth and developmental regulator, VIP may have a crucial effect as a neuronal survival factor. We shall proceed from the gene to its multiple functions.
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Affiliation(s)
- I Gozes
- Laboratory of Molecular Genetics and Developmental Neurobiology, National Institute for Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
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24
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Advis JP, Ahmed CE, Ojeda SR. Direct hypothalamic control of vasoactive intestinal peptide (VIP) levels in the developing rat ovary. Brain Res Bull 1989; 22:605-10. [PMID: 2736390 DOI: 10.1016/0361-9230(89)90077-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We have previously identified the neurotransmitter vasoactive intestinal peptide (VIP) in nerve fibers of the immature rat ovary and showed that it stimulates steroid release by a mechanism involving increased synthesis of the components of the cholesterol side-chain cleavage enzyme complex. The present experiments were undertaken to study the ontogeny of ovarian VIP levels and to determine if they change in relation to the initiation of puberty. VIP was already detected in 2-day-old ovaries; levels remained constant at approximately 4.5 pg/mg ovary until the end of juvenile development (day 30). Thereafter, and preceding the peripubertal activation of the ovary, VIP levels increased two-fold, decreased gradually towards the first proestrus, and returned to juvenile values after the first ovulation. Transection of the ovarian nerves eliminated radioimmunoassayable VIP levels in both intact and hypophysectomized rats, indicating that ovarian VIP derives mostly from the extrinsic innervation of the gland. Treatment of hypophysectomized immature female rats with human chorionic gonadotropin (hCG), follicle stimulating hormone (FSH), growth hormone (GH), prolactin (Prl), estradiol, or their combination, failed to reproduce the peripubertal increase in VIP. In contrast, unilateral direct anodal current lesions of the left preoptic-anterior hypothalamic area (POA-AHA) of hypophysectomized juvenile rats led to a significant increase in VIP in the ipsilateral ovary. Surprisingly, both bilateral lesions and lesions of the right POA-AHA also increased VIP levels in the left ovary suggesting the existence of a marked asymmetry in the hypothalamic control of ovarian VIP. Lesions of the ventromedial nucleus, dorsal AHA or small lesions of the AHA were ineffective.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J P Advis
- Department of Animal Science, Cook College, Rutgers University, NJ
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25
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Affiliation(s)
- I Gozes
- Department of Hormone Research, Weizmann Institute of Science, Rehovot, Israel
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26
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Besson J, Malassiné A, Ferré F. Autoradiographic localization of vasoactive intestinal peptide (VIP) binding sites in the human term placenta. Relationship with activation of adenylate cyclase. REGULATORY PEPTIDES 1987; 19:197-207. [PMID: 2829291 DOI: 10.1016/0167-0115(87)90276-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The presence of vasoactive intestinal peptide (VIP) binding sites and the adenylate cyclase activity in response to VIP were examined in the human term placenta. Slices were used in order to preserve the physicochemical environment and the structural integrity of this heterogeneous organ. 125I-VIP binding to placental slices was saturable. The steady state was reached after 90 min at 37 degrees C and was maintained up to 3 h. Unlabeled VIP was able to compete in a dose-dependent manner with an IC50 value of 5.2 +/- 1.3 x 10(-10) M. Autoradiography and histological analysis showed that VIP binding sites were essentially located on fetal vascularization, especially arteries of stem villi. VIP produced a stimulatory effect on cAMP synthesis at a concentration as low as 10(-10) M. The dose-response curve was monophasic with an ED50 value of 2.9 +/- 1.6 x 10(-9) M. The specificity of the VIP effect was tested with peptides structurally related to VIP such as glucagon, secretin, gastric inhibitory polypeptide and human growth-hormone releasing factor. Only secretin at high concentrations (greater than 10(-6) M) increased cAMP production. Leu-enkephalin or insulin were ineffective. The presence of both VIP binding sites on fetal vascularization and VIP-induced adenylate cyclase activation would seem to suggest a regulatory role of the peptide on fetoplacental blood flow.
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Affiliation(s)
- J Besson
- U.55 INSERM, Hôpital Saint-Antoine, Paris, France
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27
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George FW, Ojeda SR. Vasoactive intestinal peptide enhances aromatase activity in the neonatal rat ovary before development of primary follicles or responsiveness to follicle-stimulating hormone. Proc Natl Acad Sci U S A 1987; 84:5803-7. [PMID: 3039508 PMCID: PMC298951 DOI: 10.1073/pnas.84.16.5803] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
We have investigated the factors that regulate aromatase activity in fetal-neonatal rat ovaries. Ovarian aromatase activity (assessed by measuring the amount of 3H2O) formed from [1 beta-3H]testosterone) is low prior to birth (less than 0.5 pmol/hr per mg of protein) and increases to values greater than 30 pmol/hr per mg of protein between days 8 and 12 after birth. The appearance of ovarian aromatase (postnatal days 2-4) coincides with the development of primordial follicles. Fetal-neonatal ovaries maintained in serum-free organ culture do not develop aromatase activity at the expected time. Ovine follicle-stimulating hormone (0.1-1 microgram/ml), ovine luteinizing hormone (0.1 microgram/ml), or their combination failed to induce the enzyme activity in cultured fetal ovaries, whereas follicle-stimulating hormone is effective in preventing the decline in aromatase activity when postnatal day 8 ovaries are placed in culture. In contrast to follicle-stimulating hormone, dibutyryl-cAMP markedly enhances ovarian aromatase in cultured fetal ovaries. Likewise, enhancement of endogenous cAMP formation with forskolin or cholera toxin caused an increase in enzyme activity within 24 hr. Vasoactive intestinal peptide, a peptide known to occur in ovarian nerves, caused a dose-dependent increase in aromatase activity in fetal ovaries prior to folliculogenesis. Of related peptides tested, only the peptide having N-terminal histidine and C-terminal isoleucine amide was capable of inducing aromatase activity in fetal ovaries. The fact that VIP can induce aromatase activity in fetal rat ovaries prior to follicle formation and prior to responsiveness to follicle-stimulating hormone suggests that this neuropeptide may play a critical role in ovarian differentiation.
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