TY  - CONF
AU  - Janjić, Marija
AU  - Previde, Rafael Maso
AU  - Smiljanić, Kosara
AU  - Fletcher, Patrick A.
AU  - Sherman, Arthur
AU  - Bjelobaba, Ivana
AU  - Stojilkovic, Stanko S.
PY  - 2019
UR  - http://radar.ibiss.bg.ac.rs/handle/123456789/5981
AB  - Aim: To investigate mechanisms of inhibition of reproductive functions by continuous GnRH application, with focus on gonadotropin gene expression and secretion. Methods: Experiments were performed in vivo and in vitro using female and male rats and cultured pituitary cells. Gene expression was characterized by qRT-PCR analysis. For this purpose, we searched for an appropriate reference gene. Protein expression was characterized by immunocytochemistry, and ELISA and Western blot analyses were used for LH measurements. Results: Continuous exposure of pituitary cells in static cultures to Gnrh agonists induced a prolonged blockade of Fshb expression after a brief stimulation. However, only a minor and transient inhibitory effect on Lhb expression was detected. Such Lhb profile probably reflects the expression status of three genes controlling Lhb transcription during the treatment: stimulation of Egr1, inhibition of Nr5a1, and no effect on Pitx1 expression. In contrast, continuous Gnrh treatment stimulated Lh secretion in static cultures, leading to depletion of the secretory pool. In vivo administration of a Gnrh agonist was also accompanied with a rapid increase in serum Lh levels and a progressive depletion of the intrapituitary Lh levels without major effects on Lhb expression. Conclusion: Blockade of Fshb expression and depletion of the Lh secretory pool are two major factors accounting for weakening of the gonadotroph secretory function during continuous Gnrh treatment.
PB  - Belgrade: Serbian Neuroscience Society
C3  - Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia
T1  - Continuous GnRH Treatment Blocks Basal Fshb but not Lhb Expression in Rat Pituitary Gonadotrophs
SP  - 367
UR  - https://hdl.handle.net/21.15107/rcub_ibiss_5981
ER  - 

@conference{
author = "Janjić, Marija and Previde, Rafael Maso and Smiljanić, Kosara and Fletcher, Patrick A. and Sherman, Arthur and Bjelobaba, Ivana and Stojilkovic, Stanko S.",
year = "2019",
abstract = "Aim: To investigate mechanisms of inhibition of reproductive functions by continuous GnRH application, with focus on gonadotropin gene expression and secretion. Methods: Experiments were performed in vivo and in vitro using female and male rats and cultured pituitary cells. Gene expression was characterized by qRT-PCR analysis. For this purpose, we searched for an appropriate reference gene. Protein expression was characterized by immunocytochemistry, and ELISA and Western blot analyses were used for LH measurements. Results: Continuous exposure of pituitary cells in static cultures to Gnrh agonists induced a prolonged blockade of Fshb expression after a brief stimulation. However, only a minor and transient inhibitory effect on Lhb expression was detected. Such Lhb profile probably reflects the expression status of three genes controlling Lhb transcription during the treatment: stimulation of Egr1, inhibition of Nr5a1, and no effect on Pitx1 expression. In contrast, continuous Gnrh treatment stimulated Lh secretion in static cultures, leading to depletion of the secretory pool. In vivo administration of a Gnrh agonist was also accompanied with a rapid increase in serum Lh levels and a progressive depletion of the intrapituitary Lh levels without major effects on Lhb expression. Conclusion: Blockade of Fshb expression and depletion of the Lh secretory pool are two major factors accounting for weakening of the gonadotroph secretory function during continuous Gnrh treatment.",
publisher = "Belgrade: Serbian Neuroscience Society",
journal = "Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia",
title = "Continuous GnRH Treatment Blocks Basal Fshb but not Lhb Expression in Rat Pituitary Gonadotrophs",
pages = "367",
url = "https://hdl.handle.net/21.15107/rcub_ibiss_5981"
}

Janjić, M., Previde, R. M., Smiljanić, K., Fletcher, P. A., Sherman, A., Bjelobaba, I.,& Stojilkovic, S. S.. (2019). Continuous GnRH Treatment Blocks Basal Fshb but not Lhb Expression in Rat Pituitary Gonadotrophs. in Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia
Belgrade: Serbian Neuroscience Society., 367.
https://hdl.handle.net/21.15107/rcub_ibiss_5981

Janjić M, Previde RM, Smiljanić K, Fletcher PA, Sherman A, Bjelobaba I, Stojilkovic SS. Continuous GnRH Treatment Blocks Basal Fshb but not Lhb Expression in Rat Pituitary Gonadotrophs. in Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia. 2019;:367.
https://hdl.handle.net/21.15107/rcub_ibiss_5981 .

Janjić, Marija, Previde, Rafael Maso, Smiljanić, Kosara, Fletcher, Patrick A., Sherman, Arthur, Bjelobaba, Ivana, Stojilkovic, Stanko S., "Continuous GnRH Treatment Blocks Basal Fshb but not Lhb Expression in Rat Pituitary Gonadotrophs" in Book of Abstract: Federation of European Neuroscience Societies (FENS) Regional Meeting; 2019 Jul 10-13; Belgrade, Serbia (2019):367,
https://hdl.handle.net/21.15107/rcub_ibiss_5981 .

TY  - JOUR
AU  - Janjić, Marija
AU  - Prévide, Rafael M.
AU  - Fletcher, Patrick A.
AU  - Sherman, Arthur
AU  - Smiljanić, Kosara
AU  - Abebe, Daniel
AU  - Bjelobaba, Ivana
AU  - Stojilković, Stanko S.
PY  - 2019
UR  - http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=PMC6934515
UR  - https://radar.ibiss.bg.ac.rs/handle/123456789/3595
AB  - Continuous, as opposed to pulsatile, delivery of hypothalamic gonadotropin-releasing hormone (GnRH) leads to a marked decrease in secretion of pituitary gonadotropins LH and FSH and impairment of reproductive function. Here we studied the expression profile of gonadotropin subunit and GnRH receptor genes in rat pituitary in vitro and in vivo to clarify their expression profiles in the absence and continuous presence of GnRH. Culturing of pituitary cells in GnRH-free conditions downregulated Fshb, Cga, and Gnrhr expression, whereas continuous treatment with GnRH agonists upregulated Cga expression progressively and Gnrhr and Fshb expression transiently, accompanied by a prolonged blockade of Fshb but not Gnrhr expression. In contrast, Lhb expression was relatively insensitive to loss of endogenous GnRH and continuous treatment with GnRH, probably reflecting the status of Egr1 and Nr5a1 expression. Similar patterns of responses were observed in vivo after administration of a GnRH agonist. However, continuous treatment with GnRH stimulated LH secretion in vitro and in vivo, leading to decrease in LH cell content despite high basal Lhb expression. These data suggest that blockade of Fshb expression and depletion of the LH secretory pool are two major factors accounting for weakening of the gonadotroph secretory function during continuous GnRH treatment.
T2  - Scientific Reports
T1  - Divergent expression patterns of pituitary gonadotropin subunit and GnRH receptor genes to continuous GnRH in vitro and in vivo.
IS  - 1
VL  - 9
DO  - 10.1038/s41598-019-56480-1
SP  - 20098
ER  - 

@article{
author = "Janjić, Marija and Prévide, Rafael M. and Fletcher, Patrick A. and Sherman, Arthur and Smiljanić, Kosara and Abebe, Daniel and Bjelobaba, Ivana and Stojilković, Stanko S.",
year = "2019",
abstract = "Continuous, as opposed to pulsatile, delivery of hypothalamic gonadotropin-releasing hormone (GnRH) leads to a marked decrease in secretion of pituitary gonadotropins LH and FSH and impairment of reproductive function. Here we studied the expression profile of gonadotropin subunit and GnRH receptor genes in rat pituitary in vitro and in vivo to clarify their expression profiles in the absence and continuous presence of GnRH. Culturing of pituitary cells in GnRH-free conditions downregulated Fshb, Cga, and Gnrhr expression, whereas continuous treatment with GnRH agonists upregulated Cga expression progressively and Gnrhr and Fshb expression transiently, accompanied by a prolonged blockade of Fshb but not Gnrhr expression. In contrast, Lhb expression was relatively insensitive to loss of endogenous GnRH and continuous treatment with GnRH, probably reflecting the status of Egr1 and Nr5a1 expression. Similar patterns of responses were observed in vivo after administration of a GnRH agonist. However, continuous treatment with GnRH stimulated LH secretion in vitro and in vivo, leading to decrease in LH cell content despite high basal Lhb expression. These data suggest that blockade of Fshb expression and depletion of the LH secretory pool are two major factors accounting for weakening of the gonadotroph secretory function during continuous GnRH treatment.",
journal = "Scientific Reports",
title = "Divergent expression patterns of pituitary gonadotropin subunit and GnRH receptor genes to continuous GnRH in vitro and in vivo.",
number = "1",
volume = "9",
doi = "10.1038/s41598-019-56480-1",
pages = "20098"
}

Janjić, M., Prévide, R. M., Fletcher, P. A., Sherman, A., Smiljanić, K., Abebe, D., Bjelobaba, I.,& Stojilković, S. S.. (2019). Divergent expression patterns of pituitary gonadotropin subunit and GnRH receptor genes to continuous GnRH in vitro and in vivo.. in Scientific Reports, 9(1), 20098.
https://doi.org/10.1038/s41598-019-56480-1

Janjić M, Prévide RM, Fletcher PA, Sherman A, Smiljanić K, Abebe D, Bjelobaba I, Stojilković SS. Divergent expression patterns of pituitary gonadotropin subunit and GnRH receptor genes to continuous GnRH in vitro and in vivo.. in Scientific Reports. 2019;9(1):20098.
doi:10.1038/s41598-019-56480-1 .

Janjić, Marija, Prévide, Rafael M., Fletcher, Patrick A., Sherman, Arthur, Smiljanić, Kosara, Abebe, Daniel, Bjelobaba, Ivana, Stojilković, Stanko S., "Divergent expression patterns of pituitary gonadotropin subunit and GnRH receptor genes to continuous GnRH in vitro and in vivo." in Scientific Reports, 9, no. 1 (2019):20098,
https://doi.org/10.1038/s41598-019-56480-1 . .