Pituitary expression of LHβ- and FSHβ-subunit mRNA, cellular distribution of LHβ-subunit mRNA and LH and FSH synthesis during and after treatment with a gonadotrophin-releasing hormone agonist in heifers
W. J. Aspden A B , A. Jackson A , T. E. Trigg C and M. J. D’Occhio A B DA Animal Sciences and Production Group, Primary Industries Research Centre, Central Queensland University, Rockhampton, Qld 4702, Australia.
B School of Animal Studies, The University of Queensland, Gatton, Qld 4343, Australia.
C Peptech Animal Health Pty Limited, North Ryde, Sydney, NSW 2099, Australia.
D To whom correspondence should be addressed. email: mdocchio@uqg.uq.edu.au
Reproduction, Fertility and Development 15(3) 149-156 https://doi.org/10.1071/RD01106
Submitted: 15 August 2001 Accepted: 8 April 2003 Published: 8 April 2003
Abstract
The aim was to examine transcriptional and post-transcriptional regulation of LH and FSH biosynthesis. Female cattle were allocated to three groups: (i) Group 1, control (n = 6), synchronized to be at around Day 11 of the oestrous cycle on Day 31; (ii) Group 2 (n = 6), treated with gonadotrophin-releasing hormone (GnRH) agonist (deslorelin) for 31 days; and (iii) Group 3 (n = 6), treated with deslorelin for 28 days. All animals were slaughtered on Day 31. For animals in Group 2, pituitary content of LHβ-subunit mRNA was suppressed 60% (P < 0.001) and LH 95% (P < 0.001), whereas FSHβ-subunit mRNA was suppressed 25% (P > 0.05) and FSH 90% (P < 0.001). Three days after treatment with deslorelin (Group 3) LHβ-subunit mRNA and LH remained suppressed (50% and 95%, respectively; P < 0.001). At the same time, FSHβ-subunit mRNA did not differ from controls (P > 0.05) whereas FSH remained reduced by 80% (P < 0.001). The ratio of LHβ-subunit mRNA present in the nucleus versus cytoplasm of gonadotroph cells was reduced (P < 0.05) in heifers during treatment with deslorelin (0.59 ± 0.05) compared with the ratio in control heifers (1.31 ± 0.22) and heifers 3 days after discontinuation of treatment (1.01 ± 0.05). The findings indicated that treatment with GnRH agonist can suppress LHβ-subunit mRNA expression without any significant effect on FSHβ-subunit mRNA. As LH and FSH contents were suppressed to a greater degree than their β-subunit mRNAs, it would appear that treatment with a GnRH agonist might influence gonadotrophin biosynthesis by a post-transcriptional mechanism(s). For LHβ-subunit mRNA, this would appear not to be reduced export of message from the nucleus.
Acknowledgments
The authors thank Mr Graeme Halford and Mr John Quilty (Belmont Research Station) for the management of experimental animals and assistance with experimental procedures. The study was supported, in part, by an Australian Research Council SPIRT grant (M.J.D.) and the Research Services Office, Central Queensland University. We also thank Dr. Steve Johnston for advice on the digital recording of hybridization images.
Aspden, W. J. , Rao, A. , Scott, P. T. , Clarke, I. J. , Trigg, T. E. , Walsh, J. , and D’Occhio, M. J. (1996). Direct actions of the luteinizing hormone-releasing hormone agonist, deslorelin, on anterior pituitary contents of luteinizing hormone (LH), and follicle-stimulating hormone (FSH), LH and FSH subunit messenger ribonucleic acid, and plasma concentrations of LH and FSH in castrated male cattle Biol. Reprod. 55, 386–92.
| PubMed |
Aspden, W. J. , Rao, A. , Rose, K. , Scott, P. T. , Clarke, I. J. , Trigg, T. E. , Walsh, J. , and D’Occhio, M. J. (1997). Differential responses in anterior pituitary luteinizing hormone (LH) content and LHβ- and α-subunit mRNA, and plasma concentrations of LH and testosterone, in bulls treated with the LH-releasing hormone agonist deslorelin Dom. Anim. Endocrinol. 14, 429–37.
Bergfeld, E. G. M. , D’Occhio, M. J. , and Kinder, J. E. (1996a). Continued desensitization of the pituitary gland in young bulls after treatment with the luteinizing hormone-releasing hormone agonist deslorelin Biol. Reprod. 54, 769–75.
| PubMed |
Bergfeld, E. G. M. , D’Occhio, M. J. , and Kinder, J. E. (1996b). Pituitary function, ovarian follicular growth, and plasma concentrations of 17β-estradiol and progesterone in prepubertal heifers during and after treatment with the luteinizing hormone-releasing hormone agonist deslorelin Biol. Reprod. 54, 776–82.
| PubMed |
Broekmans, F. J. , Hompes, P. G. , Lambalk, C. B. , Schoute, E. , Broeders, A. , and Schoemaker, J. (1996). Short term pituitary desensitization: effects of different doses of the gonadotrophin-releasing hormone agonist triptorelin Hum. Reprod. 11, 55–60.
| PubMed |
Brooks, J. , and McNeilly, A. S. (1994). Regulation of gonadotrophin-releasing hormone receptor mRNA expression in the sheep J. Endocrinol. 143, 175–82.
| PubMed |
Brown, P. , and McNeilly, A. S. (1999). Transcriptional regulation of pituitary gonadotrophin subunit genes Rev. Reprod. 4, 117–24.
| PubMed |
Brown, J. L. , and Reeves, J. J. (1983). Absence of specific LHRH receptors in ovine, bovine and porcine ovaries Biol. Reprod. 29, 1179–82.
| PubMed |
Burger, L. L. , Dalkin, C. A. , Aylor, K. W. , Workman, L. J. , Haisenleder, D. J. , and Marshall, J. C. (2001). Regulation of gonadotropin subunit transcription after ovariectomy in the rat: measurement of subunit primary transcripts reveals differential roles of GnRH and inhibin Endocrinology 142, 3435–42.
| PubMed |
Clarke, I. J. , Rao, A. , Fallest, P. C. , and Shupnik, M. A. (1993). Transcription rate of the follicle stimulating hormone (FSH) β subunit gene is reduced by inhibin in sheep but this does not fully explain the decrease in mRNA Mol. Cell. Endocrinol. 91, 211–16.
| PubMed |
Dalkin, A. C. , Knight, C. D. , Shupnik, M. A. , Haisenleder, D. J. , Aloi, J. , Kirk, S. E. , Yasin, M. , and Marshall, J. C. (1993). Ovariectomy and inhibin immunoneutralization acutely increase follicle-stimulating hormone-β messenger ribonucleic acid concentrations: evidence for a nontranscriptional mechanism Endocrinology 132, 1297–304.
| PubMed |
Day, D. A. , and Tuite, M. F. (1998). Post-transcriptional gene regulatory mechanisms in eukaryotes: an overview J. Endocrinol. 157, 361–71.
| PubMed |
D’Occhio, M. J. , and Aspden, W. J. (1996). Characteristics of luteinizing hormone (LH) and testosterone secretion, pituitary responses to LH-releasing hormone (LHRH) and reproductive function in young bulls receiving the LHRH agonist deslorelin effect of castration on LH responses to LHRH Biol. Reprod. 54, 45–52.
| PubMed |
D’Occhio, M. J. , Gifford, D. R. , Weatherly, T. , and Setchell, B. P. (1986). Evidence of gonadal steroid-independent changes in activity of the central LH-releasing hormone pulse generator in developing bull calves J. Endocrinol. 111, 67–73.
| PubMed |
D’Occhio, M. J. , Gifford, D. R. , Earl, C. R. , Weatherly, T. , and von Rechenberg, W. (1989). Pituitary and ovarian responses of post-partum acyclic beef cows to continuous long-term GnRH and GnRH agonist treatment J. Reprod. Fertil. 85, 495–502.
| PubMed |
D’Occhio, M. J. , Chalen, G. A. , Braga, D. P. A. F. , Aspden, W. J. , and Trigg, T. E. (2000a). Post-transcription regulation of mRNA and hormone synthesis and release at the anterior pituitary gland: Information derived from the recovery of pituitary gonadotrope cell function after therapy with a GnRH agonist Ann. Rev. Biomed. Sci. 2, 91–112.
D’Occhio, M. J. , Fordyce, G. , Whyte, T. R. , Aspden, W. J. , and Trigg, T. E. (2000b). Reproductive responses of cattle to GnRH agonists Anim. Reprod. Sci. 60–61, 433–42.
| Crossref | GoogleScholarGoogle Scholar |
Evans, J. J. (1999). Modulation of gonadotropin levels by peptides acting at the anterior pituitary gland Endocr. Rev. 20, 46–67.
| PubMed |
Garverick, H. A. , Baxter, G. , Gong, J. , Armstrong, D. G. , Campbell, B. K. , Gutierrez, C. G. , and Webb, R. (2002). Regulation of expression of ovarian mRNA encoding steroidogenic enzymes and gonadotrophin receptors by FSH and GH in hypogonadotrophic cattle Reproduction 123, 651–61.
| PubMed |
Godine, J. E. , Chin, W. W. , and Habener, J. F. (1982). α-Subunit of rat pituitary glycoprotein hormones. Primary structure of the precursor determined from the nucleotide sequence of cloned cDNAs J. Biol. Chem. 257, 8368–71.
| PubMed |
Gong, J. G. , Campbell, B. K. , Bramley, T. A. , Gutierrez, C. G. , Peters, A. R. , and Webb, R. (1996). Suppression in the secretion of follicle-stimulating hormone and luteinizing hormone, and ovarian follicle development in heifers continuously infused with a gonadotropin-releasing hormone agonist Biol. Reprod. 55, 68–74.
| PubMed |
Hall, M. C. , Fritzsch, R. J. , Sagalowsky, A. I. , Ahrens, A. , Petty, B. , and Roehrborn, C. G. (1999). Prospective determination of the hormonal response after cessation of luteinizing hormone-releasing hormone agonist treatment in patients with prostate cancer Urology 53, 898–902.
| Crossref | GoogleScholarGoogle Scholar | PubMed |
Karten, M. , and Rivier, J. (1986). Gonadotropin-releasing hormone analogue design. Structure-function studies toward the development of agonists and antagonists: rationale and perspective Endocr. Rev. 7, 44–66.
| PubMed |
Laloz, M. R. , Detta, A. , and Clayton, R. N. (1988). Gonadotropin-releasing hormone desensitization preferentially inhibits expression of the luteinizing hormone β-subunit gene in vivo Endocrinology 122, 1689–94.
| PubMed |
Maurer, R. (1985). Analysis of several bovine lutropin β-subunit cDNAs reveals heterogeneity in nucleotide sequence J. Biol. Chem. 260, 4684–7.
| PubMed |
Maurer, R. , and Beck, A. (1986). Isolation and nucleotide sequence analysis of a cloned cDNA encoding the β-subunit of bovine follicle-stimulating hormone DNA 5, 363–9.
| PubMed |
McLeod, B. J. , Peters, A. R. , Haresign, W. , and Lamming, G. E. (1985). Plasma LH and FSH responses and ovarian activity in prepubertal heifers treated with repeated injections of low doses of GnRH for 72 h J. Reprod. Fertil. 74, 589–96.
| PubMed |
McNeilly, J. R. , Brown, P. , Clark, A. J. , and McNeilly, A. S. (1991). Gonadotrophin-releasing hormone modulation of gonadotrophins in the ewe: evidence for differential effects on gene expression and hormone secretion J. Mol. Endocrinol. 7, 35–43.
| PubMed |
Melson, B. E. , Brown, J. L. , Schoenemann, H. M. , Tarnavsky, G. K. , and Reeves, J. J. (1986). Elevation of serum testosterone during chronic LHRH agonist treatment in the bull J. Anim. Sci. 62, 199–207.
| PubMed |
Park, D. , Cheon, M. , Kim, C. , Kim, K. , and Ryu, K. (1996). Progesterone together with estradiol promotes luteinizing hormone β-subunit mRNA stability in rat pituitary cells cultured in vitro Eur. J. Endocrinol. 134, 236–42.
| PubMed |
Paul, S. J. , Ortolano, G. A. , Haisenleder, D. J. , Stewart, J. M. , Shupnik, M. A. , and Marshall, J. C. (1990). Gonadotropin subunit messenger RNA concentrations after blockade of gonadotropin-releasing hormone action: testosterone selectively increases follicle-stimulating hormone β-subunit messenger RNA by posttranscriptional mechanisms Mol. Endocrinol. 4, 1943–55.
| PubMed |
Saavedra, C. , Tung, K. S. , Amberg, D. C. , Hopper, A. K. , and Cole, C. N. (1996). Regulation of mRNA export in response to stress in Saccharomyces cerevisiae Genes Dev. 10, 1608–20.
| PubMed |
Saunders, B. D. , Sabbagh, E. , Chin, W. W. , and Kaiser, U. B. (1998). Differential use of signal transduction pathways in the gonadotropin-releasing hormone-mediated regulation of gonadotropin subunit gene expression Endocrinology 139, 1835–43.
| PubMed |
Staton, J. M. , Thomson, A. M. , and Leedman, P. J. (2000). Hormonal regulation of mRNA stability and RNA–protein interactions in the pituitary J. Mol. Endocrinol. 25, 17–34.
| PubMed |
Xu, Z. , Garverick, H. A. , Smith, G. W. , Smith, M. F. , Hamilton, S. A. , and Youngquist, R. S. (1995). Expression of messenger ribonucleic acid encoding cytochrome P450 side-chain cleavage, cytochrome P450 17 α-hydroxylase, and cytochrome P450 aromatase in bovine follicles during the first follicular wave Endocrinology 136, 981–9.
| PubMed |
