Expression of the common α-subunit mRNA of glycoprotein hormones during the chick pituitary organogenesis, with special reference to the pars tuberalis

1999 ◽  
Vol 299 (1) ◽  
pp. 71-80
Author(s):  
Yoko Kameda ◽  
Masaaki Miura ◽  
Sae Ohno
Keyword(s):  
Special Reference ◽  
Pars Tuberalis ◽  
Glycoprotein Hormones ◽  
Α Subunit ◽  
Subunit Mrna ◽  
The Common

Pars tuberalis-specific cells in the ovine pituitary do express the common α-chain of glycoprotein hormones: an in situ hybridization and immunocytochemical study

1994 ◽  
Vol 131 (5) ◽  
pp. 540-546 ◽  
Author(s):  
TM Böckers ◽  
J Bockmann ◽  
J-D Fauteck ◽  
MR Kreutz ◽  
R Bock ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Secretory Activity ◽  
Immunocytochemical Staining ◽  
Pars Tuberalis ◽  
Glycoprotein Hormones ◽  
Immunocytochemical Study ◽  
Α Subunit ◽  
The Common ◽  
Α Chain

Böckers TM, Bockmann J, Fauteck J-D, Kreutz MR, Bock R, Wittkowski W. Pars tuberalis-specific cells in the ovine pituitary do express the common α-chain of glycoprotein hormones: an in situ hybridization and immunocytochemical study. Eur J Endocrinol 1994;131:540–6. ISSN 0804–4643 The ovine pituitary pars tuberalis was investigated by electron microscopy, immunocytochemistry and non-radioactive in situ hybridization in order to characterize further the pars tuberalis-specific cells, whose functional role within the endocrine system is still enigmatic. Ultrastructural analysis revealed that, besides gonadotropic cells, the vast majority of cells in the ovine pars tuberalis show the typical characteristics of pars tuberalis-specific cells with clear signs of secretory activity. Immunocytochemical staining with a polyclonal antibody directed against the α-subunit of ovine glycoprotein hormones and in situ hybridization with an antisense oligonucleotide complementary to the α-subunit mRNA showed that the common α-chain of glycoprotein hormones is expressed in pars tuberalis-specific cells. Antibodies against the β-subunits failed to detect any of the known β-chains of pituitary glycoprotein hormones in these cells. The demonstration of the glycoprotein α-subunit in pars tuberalis-specific cells of the adult sheep supports previously existing evidence that these cells do secrete one or more glycoprotein hormones. With respect to the thyrotropin-β-like immunoreactivity in rats and hamsters, one might speculate that pars tuberalis-specific cells are a pluripotent cell type with a low secretory activity under basal conditions. Further studies should prove the hypothesis that a pre-existing mRNA pool in these cells can be used for sustained translation of glycoprotein hormones after physiological or pharmacological stimulation. W Wittkowski, Institute of Anatomy, University of Münster, Vesaliusweg 2–4, 48 129 Münster, Germany

Effects of the gonadotrophin-releasing hormone agonist 'Zoladex' upon pituitary and gonadal function in hypogonadal (hpg) male mice: a comparison with normal male and testicular feminized (tfm) mice

1992 ◽  
Vol 8 (3) ◽  
pp. 249-258 ◽  
Author(s):  
I. S. Scott ◽  
M. K. Bennett ◽  
A. E. Porter-Goff ◽  
C. J. Harrison ◽  
B. S. Cox ◽  
...  
Keyword(s):  
Seminal Vesicle ◽  
Mrna Levels ◽  
Gonadal Function ◽  
Glycoprotein Hormone ◽  
Α Subunit ◽  
Releasing Hormone ◽  
Subunit Mrna ◽  
Serum Lh ◽  
Gonadotrophin Releasing Hormone ◽  
The Common

ABSTRACT Hypogonadal (hpg) mutant mice, with a congenital deficiency of hypothalamic gonadotrophin-releasing hormone (GnRH), and testicular feminized (tfm) mice, which lack a functional androgen receptor, were used to study the effects of the potent GnRH agonist 'Zoladex' (ICI 118630; d-Ser (But)6, Azgly10-GnRH) on pituitary and gonadal function. Zoladex (0.5 mg) in a sustained-release lactide—glycolide copolymer depot was administered subcutaneously under anaesthesia and was left in place for 7 days, after which time the effects of the drug upon pituitary and serum gonadotrophin concentrations, glycoprotein hormone subunit mRNAs and testicular morphology were investigated. At the pituitary level, Zoladex treatment resulted in a substantial reduction in LH content in normal males, and LH content was depressed in hpg mice even below the basal levels normally found in these mutants. Pituitary LH content in the Zoladex-treated animals was depressed in the tfm groups, but not to the same levels as those found in the normal and castrated normal mice. Zoladex treatment at the time of castration prevented the post-operative elevation in serum LH associated with castration alone. In the androgen-deficient tfm mouse, Zoladex did not depress the normally elevated serum LH levels. Serum LH in the hpg animals was, in all cases, below the limit of detection of the assay. Pituitary FSH content was depressed into the hpg range in both the normal and castrated animals, but there was no further depression in the hpg mice. The pituitary content was reduced in the tfm mice, again the effects not being as dramatic as in the normal and castrated animals. Serum FSH content, as measured by radioimmunoassay, was depressed by 50% in normal mice; there was no reduction in the hpg mice, however. With regard to pituitary gonadotrophic hormone gene expression, Zoladex administration to normal mice caused a dramatic reduction in LHβ mRNA content, to a level approximating that found in untreated hpg mice. The drug also depressed LHβ mRNA in the castrated group to the hpg range when given at the time of castration, whereas in untreated castrated mice there was a significant increase in LHβ mRNA. In the tfm mouse, which can be considered as a model for long-term failure of androgen feedback, Zoladex again induced a fall in LHβ mRNA, but not to the same extent as in the normal and normal castrated group. Zoladex had no effect on the already low levels of LHβ mRNA found in hpg mice. Pituitary FSHβ mRNA levels were not significantly altered by Zoladex in any of the treatment groups, whereas the drug induced a substantial rise in the common α-subunit mRNA in normal and hpg mice, to a level equalling that found in castrated tfm mice. In the latter two groups, Zoladex treatment did not result in a further increase in α-subunit mRNA above that found after castration alone, or in the untreated tfm mutant. Treatment for 7 days with Zoladex resulted in a significant increase in testis weight, with spermatogenesis advancing beyond the first meiotic division with many round spermatids found within the seminiferous tubules. However, the interstitial cells remained atrophic and there was evidence of seminal vesicle growth. Nevertheless, there was a small but significant increase in testicular androgen content. Administration of the agonist to hypophysectomized hpg mice did not stimulate testicular or seminal vesicle growth, suggesting that the drug does not stimulate steroidogenesis via a direct action upon the testis. Overall, the pharmacological effects of the drug appear to have turned off the transcription of the LHβ gene, with a consequent reduction in LH synthesis and probably also secretion in the longer term. With FSHβ, gene transcription was apparently unchanged and, with a substantial increase in the common α-subunit message, it would appear that the pituitary gland of Zoladex-treated animals may be predominantly biased towards FSH secretion. Although the circulating FSH levels as measured by radioimmunoassay were unaltered by Zoladex, there are several reports that GnRH agonists increase serum levels of bioactive hormones, perhaps by altering glycosylation of the FSH dimer glycoprotein.

scholarly journals Characterization and nucleotide sequence of the gene for the common α subunit of the bovine pituitary glycoprotein hormones

1983 ◽  
Vol 11 (19) ◽  
pp. 6873-6882 ◽  
Author(s):  
R.G. Goodwin ◽  
C.L. Moncman ◽  
F.M. Rottman ◽  
J.H. Nilson
Keyword(s):  
Nucleotide Sequence ◽  
Glycoprotein Hormones ◽  
Α Subunit ◽  
The Common

COMPARISON OF CIRCULATING GLYCOPROTEIN HORMONES AND THEIR SUBUNITS IN PATIENTS WITH OAT CELL CARCINOMA OF THE LUNG AND URAEMIC PATIENTS ON CHRONIC DIALYSIS

1976 ◽  
Vol 83 (1) ◽  
pp. 26-35 ◽  
Author(s):  
C. Hagen ◽  
E. D. Gilby ◽  
A. S. McNeilly ◽  
K. Ølgaard ◽  
P. K. Bondy ◽  
...  
Keyword(s):  
Renal Failure ◽  
Chronic Renal Failure ◽  
Cell Carcinoma ◽  
Normal Subjects ◽  
Glycoprotein Hormones ◽  
Α Subunit ◽  
Female Patients ◽  
Disease States ◽  
Oat Cell Carcinoma ◽  
The Common

ABSTRACT It has recently been suggested that the measurement of the glycoprotein hormones and their subunits in human serum may serve as biochemical markers of non-endocrine tumours. Using radioimmunoassays for LH, FSH, HCGβ-, LHβ- and the common α-subunit, significant differences in the levels of these substances could not be detected between patients with oat cell lung tumours and patients with chronic renal failure. However, compared to normal subjects the α-subunit levels in serum were elevated in 12% of the male and 30% of the female patients with oat cell carcinoma of the lung and in 80 and 50% of the male and female patients, respectively, with chronic renal failure. The LHβ-subunit concentration was normal in all tumour patients and none of these patients had detectable (< 4 ng/ml) levels of HCGβ-subunit. While such measurements may be of value in relationship to particular neoplasms, it appears that raised levels of glycoproteins and their subunits may be found in other disease states.

scholarly journals Ontogeny of the Saccus Vasculosus, a Seasonal Sensor in Fish

Endocrinology ◽  
2015 ◽  
Vol 156 (11) ◽  
pp. 4238-4243 ◽  
Author(s):  
Ryosuke Maeda ◽  
Takayuki Shimo ◽  
Yusuke Nakane ◽  
Nobuhiro Nakao ◽  
Takashi Yoshimura
Keyword(s):  
Pituitary Gland ◽  
Histological Analysis ◽  
Morphological Differentiation ◽  
Functional Differentiation ◽  
Regulatory Mechanisms ◽  
Seasonal Reproduction ◽  
Pars Tuberalis ◽  
Saccus Vasculosus ◽  
Α Subunit ◽  
The Common

TSH secreted from the pars distalis (PD) of the pituitary gland stimulates the thyroid gland. In contrast, TSH secreted from the pars tuberalis (PT) of the pituitary gland regulates seasonal reproduction. The ontogeny of thyrotrophs and the regulatory mechanisms of TSH are apparently different between the PD and the PT. Interestingly, fish do not have an anatomically distinct PT, and the saccus vasculosus (SV) of fish is suggested to act as a seasonal sensor. Thus, it is possible that the SV is analogous to the PT. Here we examined the ontogeny of the pituitary gland and SV using rainbow trout. A histological analysis demonstrated the development of the pituitary anlage followed by that of the SV. Lhx3 and Pit-1, which are required for the development of PD thyrotrophs, clearly labeled the pituitary anlage. The common glycoprotein α-subunit (CGA) and TSH β-subunit (TSHB) genes were also detected in the pituitary anlage. In contrast, none of these genes were detected in the SV anlage. We then performed a microarray analysis and identified parvalbumin (Pvalb) as a marker for SV development. Because Pvalb expression was not detected in the pituitary anlage, no relationship was observed between the development of the SV and the pituitary gland. In contrast to embryos, Lhx3, Pit-1, CGA, and TSHB were all expressed in the adult SV. These results suggest that the morphological differentiation of SV occurs during the embryonic stage but that the functional differentiation into a seasonal sensor occurs in a later developmental stage.

scholarly journals Cloning and DNA sequence analysis of the cDNA for the common α-subunit of the ovine pitultary glycoprotein hormones

1989 ◽  
Vol 17 (24) ◽  
pp. 10494-10494 ◽  
Author(s):  
Paul A. Bello ◽  
Peter S. Mountford ◽  
Malcolm R. Brandon ◽  
Timothy E. Adams
Keyword(s):  
Sequence Analysis ◽  
Dna Sequence ◽  
Dna Sequence Analysis ◽  
Glycoprotein Hormones ◽  
Α Subunit ◽  
The Common
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