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Immunolabelling of prolactin at ultrastructural level using the protein A-gold technique on Epon-embedded tissue

Ng KH, Tan KL, Gan SK, Looi LM

Malays J Pathol, 1992 Jun;14(1):29-33.
PMID: 1469915

The use of the colloidal-gold technique in electron microscopy immunocytochemistry has provided important information on the in situ localisation of intracellular antigens. We have developed a post-embedding technique for prolactin localisation on resin-embedded human pituitary tissue sections by the use of the protein-A gold conjugate. Human pituitary tissue obtained at autopsy was processed for electron microscopical study without post-osmication and then embedded in Epon. The indirect immunoperoxidase method was used for light microscopical targetting of lactotroph cells for subsequent electron microscopical antigen localisation. Ultra-thin sections were labelled with human anti-human prolactin followed by protein-A gold conjugate. Specific labelling was observed over secretory granules with a density of 15-30 particles per granule, as determined by the Quantimet 570 image analysis system. This technique provides a means of studying the pathophysiology of hormonal secretion at ultrastructural level and can be a useful tool in diagnostic and research investigations.

Matched MeSH terms: Pituitary Gland/ultrastructure; Pituitary Gland/chemistry*
Fulltext Proteomic Analysis of the Human Anterior Pituitary Gland

Yelamanchi SD, Tyagi A, Mohanty V, Dutta P, Korbonits M, Chavan S, et al.

OMICS, 2018 12;22(12):759-769.
PMID: 30571610 DOI: 10.1089/omi.2018.0160

The pituitary function is regulated by a complex system involving the hypothalamus and biological networks within the pituitary. Although the hormones secreted from the pituitary have been well studied, comprehensive analyses of the pituitary proteome are limited. Pituitary proteomics is a field of postgenomic research that is crucial to understand human health and pituitary diseases. In this context, we report here a systematic proteomic profiling of human anterior pituitary gland (adenohypophysis) using high-resolution Fourier transform mass spectrometry. A total of 2164 proteins were identified in this study, of which 105 proteins were identified for the first time compared with high-throughput proteomic-based studies from human pituitary glands. In addition, we identified 480 proteins with secretory potential and 187 N-terminally acetylated proteins. These are the first region-specific data that could serve as a vital resource for further investigations on the physiological role of the human anterior pituitary glands and the proteins secreted by them. We anticipate that the identification of previously unknown proteins in the present study will accelerate biomedical research to decipher their role in functioning of the human anterior pituitary gland and associated human diseases.

Matched MeSH terms: Pituitary Gland, Anterior/metabolism*
Fulltext Factors Influencing Disconnection Hyperprolactinemia and Reversal of Serum Prolactin after Pituitary Surgery in a Non-Functioning Pituitary Macroadenoma

Kumran T, Haspani S, Malin Abdullah J, Alias A, Ven FR

Malays J Med Sci, 2016 Jan;23(1):72-6.
PMID: 27540328 MyJurnal

To investigate factors influencing disconnection hyperprolactinemia, including tumour volume, degree of pituitary stalk displacement and extent of tumour growth based on a modified Wilson-Hardy classification in a non-functioning pituitary macroadenoma and to confirm reductions in serum prolactin levels after endoscopic transphenoidal surgery.

Matched MeSH terms: Pituitary Gland
Fulltext Minimally invasive surgical approaches to the sphenoid sinus, sella, parasellar and clival region: current and future perspectives

Gendeh BS

Med J Malaysia, 2006 Aug;61(3):274-7.
PMID: 17240574
Matched MeSH terms: Pituitary Gland/surgery*
Outcomes of pituitary surgery for Cushing's disease: a systematic review and meta-analysis

Stroud A, Dhaliwal P, Alvarado R, Winder MJ, Jonker BP, Grayson JW, et al.

Pituitary, 2020 Oct;23(5):595-609.
PMID: 32691356 DOI: 10.1007/s11102-020-01066-8

PURPOSE: Transsphenoidal surgery (TSS) is the first-line treatment for Cushing's disease (CD). This review aimed to synthesize the remission and recurrence rates following TSS for CD and identify predictors of these outcomes.
METHODS: Medline (1946-) and Embase (1947-) were searched until 23rd January 2019 for original studies. A meta-analysis was performed of remission and recurrence rates. Studies were excluded if patients had prior radiosurgery/radiotherapy, mixed pathologies or interventions without separated data, follow-up not reported or population size

Matched MeSH terms: Pituitary Gland/surgery*
Hypersecretion of growth hormone in an acromegalic of 25 years' duration

Teo SK, Cheah JS

Med J Malaysia, 1973 Mar;27(3):220-2.
PMID: 4268929
Matched MeSH terms: Pituitary Gland/secretion*
Fulltext Structural and functional divergence of gonadotropin-inhibitory hormone from jawless fish to mammals

Ogawa S, Parhar IS

Front Endocrinol (Lausanne), 2014;5:177.
PMID: 25386165 DOI: 10.3389/fendo.2014.00177

Gonadotropin-inhibitory hormone (GnIH) was discovered as a novel hypothalamic peptide that inhibits gonadotropin release in the quail. The presence of GnIH-homologous peptides and its receptors (GnIHRs) have been demonstrated in various vertebrate species including teleosts, suggesting that the GnIH-GnIHR family is evolutionarily conserved. In avian and mammalian brain, GnIH neurons are localized in the hypothalamic nuclei and their neural projections are widely distributed. GnIH acts on the pituitary and gonadotropin-releasing hormone neurons to inhibit reproductive functions by decreasing gonadotropin release and synthesis. In addition, GnIH-GnIHR signaling is regulated by various factors, such as environmental cues and stress. However, the function of fish GnIH orthologs remains inconclusive because the physiological properties of fish GnIH peptides are debatable. This review summarizes the current research progress in GnIH-GnIHR signaling and their physiological functions in vertebrates with special emphasis on non-mammalian vertebrate species.

Matched MeSH terms: Pituitary Gland
Diabetes insipidus and syndrome of inappropriate antidiuretic hormone complicating pituitary surgery

Aboud SK, Yunus MR, Gendeh BS

Otolaryngol Head Neck Surg, 2011 Jun;144(6):1005-6.
PMID: 21493376 DOI: 10.1177/0194599810390899
Matched MeSH terms: Pituitary Gland/pathology; Pituitary Gland/surgery*
Fulltext Reactive oxygen species and male reproductive hormones

Darbandi M, Darbandi S, Agarwal A, Sengupta P, Durairajanayagam D, Henkel R, et al.

Reprod Biol Endocrinol, 2018 Sep 11;16(1):87.
PMID: 30205828 DOI: 10.1186/s12958-018-0406-2

Reports of the increasing incidence of male infertility paired with decreasing semen quality have triggered studies on the effects of lifestyle and environmental factors on the male reproductive potential. There are numerous exogenous and endogenous factors that are able to induce excessive production of reactive oxygen species (ROS) beyond that of cellular antioxidant capacity, thus causing oxidative stress. In turn, oxidative stress negatively affects male reproductive functions and may induce infertility either directly or indirectly by affecting the hypothalamus-pituitary-gonadal (HPG) axis and/or disrupting its crosstalk with other hormonal axes. This review discusses the important exogenous and endogenous factors leading to the generation of ROS in different parts of the male reproductive tract. It also highlights the negative impact of oxidative stress on the regulation and cross-talk between the reproductive hormones. It further describes the mechanism of ROS-induced derangement of male reproductive hormonal profiles that could ultimately lead to male infertility. An understanding of the disruptive effects of ROS on male reproductive hormones would encourage further investigations directed towards the prevention of ROS-mediated hormonal imbalances, which in turn could help in the management of male infertility.

Matched MeSH terms: Pituitary Gland/metabolism; Pituitary Gland/physiology
Distribution of LPXRFa, a gonadotropin-inhibitory hormone ortholog peptide, and LPXRFa receptor in the brain and pituitary of the tilapia

Ogawa S, Sivalingam M, Biran J, Golan M, Anthonysamy RS, Levavi-Sivan B, et al.

J. Comp. Neurol., 2016 10 01;524(14):2753-75.
PMID: 26917324 DOI: 10.1002/cne.23990

In vertebrates, gonadotropin-releasing hormone (GnRH) and gonadotropin-inhibitory hormone (GnIH), respectively, regulate reproduction in positive and negative manners. GnIH belongs to the LPXRFa family of peptides previously identified in mammalian and nonmammalian vertebrates. Studying the detailed distribution of LPXRFa as well as its receptor (LPXRFa-R) in the brain and pituitary is important for understanding their multiple action sites and potential functions. However, the distribution of LPXRFa and LPXRFa-R has not been studied in teleost species, partially because of the lack of fish-specific antibodies. Therefore, in the present study, we generated specific antibodies against LPXRFa and its receptor from Nile tilapia (Oreochromis niloticus), and examined their distributions in the brain and pituitary by immunohistochemistry. Tilapia LPXRFa-immunoreactive neurons lie in the posterior ventricular nucleus of the caudal preoptic area, whereas LPXRFa-R-immunoreactive cells are distributed widely. Double immunofluorescence showed that neither LPXRFa-immunoreactive fibers nor LPXRFa-R is closely associated or coexpressed with GnRH1, GnRH3, or kisspeptin (Kiss2) neurons. In the pituitary, LPXRFa fibers are closely associated with gonadotropic endocrine cells [expressing luteinizing hormone (LH) and follicle-stimulating hormone (FSH)], with adrenocorticomelanotropic cells [corticotropin (ACTH) and α-melanotropin (α-MSH)], and with somatolactin endocrine cells. In contrast, LPXRFa-R are expressed only in LH, ACTH, and α-MSH cells. These results suggest that LPXRFa and LPXRFa-R signaling acts directly on the pituitary cells independent from GnRH or kisspeptin and could play multiple roles in reproductive and nonreproductive functions in teleosts. J. Comp. Neurol. 524:2753-2775, 2016. © 2016 Wiley Periodicals, Inc.

Matched MeSH terms: Pituitary Gland/metabolism; Pituitary Gland/chemistry*
Fulltext Contribution of GnIH Research to the Progress of Reproductive Neuroendocrinology

Tsutsui K, Ubuka T, Son YL, Bentley GE, Kriegsfeld LJ

Front Endocrinol (Lausanne), 2015;6:179.
PMID: 26635728 DOI: 10.3389/fendo.2015.00179

Since the discovery of gonadotropin-releasing hormone (GnRH) in mammals at the beginning of the 1970s, it was generally accepted that GnRH is the only hypothalamic neuropeptide regulating gonadotropin release in mammals and other vertebrates. In 2000, however, gonadotropin-inhibitory hormone (GnIH), a novel hypothalamic neuropeptide that actively inhibits gonadotropin release, was discovered in quail. Numerous studies over the past decade and a half have demonstrated that GnIH serves as a key player regulating reproduction across vertebrates, acting on the brain and pituitary to modulate reproductive physiology and behavior. In the latter case, recent evidence indicates that GnIH can regulate reproductive behavior through changes in neurosteroid, such as neuroestrogen, biosynthesis in the brain. This review summarizes the discovery of GnIH, and the contributions to GnIH research focused on its mode of action, regulation of biosynthesis, and how these findings advance our understanding of reproductive neuroendocrinology.

Matched MeSH terms: Pituitary Gland
Fulltext Extragonadal germ cell tumor presenting in a woman with systemic lupus erythematosus: a case report

Shahrir M, Halim A, Zainudin S, Mohamad R, Yuen LC, Saidin R, et al.

J Med Case Rep, 2010;4:97.
PMID: 20338049 DOI: 10.1186/1752-1947-4-97

Germ cell tumor of the pituitary gland is a very rare occurrence.

Matched MeSH terms: Pituitary Gland
The creation and verification of cranial models using three-dimensional rapid prototyping technology in field of transnasal sphenoid endoscopy

Waran V, Menon R, Pancharatnam D, Rathinam AK, Balakrishnan YK, Tung TS, et al.

Am J Rhinol Allergy, 2012 Sep-Oct;26(5):e132-6.
PMID: 23168144 DOI: 10.2500/ajra.2012.26.3808

Surgical navigation systems have been used increasingly in guiding complex ear, nose, and throat surgery. Although these are helpful, they are only beneficial intraoperatively; thus, the novice surgeon will not have the preoperative training or exposure that can be vital in complex procedures. In addition, there is a lack of reliable models to give surgeons hands-on training in performing such procedures.

Matched MeSH terms: Pituitary Gland/anatomy & histology; Pituitary Gland/radiography; Pituitary Gland/surgery
Now You See, Now You Don't: A Case Of Spontaneous Regression of Pituitary Tumour

Jaafar AS, Mohd Shokri SS, Paramasvaran S, Palaniandy K, Fadzil F

Cureus, 2020 Jul 14;12(7):e9174.
PMID: 32802610 DOI: 10.7759/cureus.9174

Spontaneous regression of pituitary tumours are rare and can be due to tumour ischaemia, pituitary apoplexy, or lymphocytic hypophysitis. We report a case of a 32-year-old female, who presented with symptoms and signs of extrasellar pituitary enlargement and hypothyroidism. MRI revealed a pituitary mass that spontaneously regressed after a month, with complete resolution of symptoms. Not all pituitary tumours require surgical intervention especially in the case of autoimmune lymphocytic hypophysitis.

Matched MeSH terms: Pituitary Gland
Fulltext Case Report of a Pituitary Metastasis from Lung Adenocarcinoma Masquerading as Pituitary Adenoma

Rajakumar R, Rahmatullah IH, Rahim AA

J ASEAN Fed Endocr Soc, 2020;35(1):133-136.
PMID: 33442183 DOI: 10.15605/jafes.035.01.24

Metastasis to the pituitary gland is an unusual situation in clinical practice and is typically observed in those with underlying malignancy with breast and lung being the commonest primary site. However, we report a case of an apparently well 49-year-old female with metastatic lung adenocarcinoma who presented with visual disturbance and diabetes insipidus related to pituitary metastasis as an initial presentation.

Matched MeSH terms: Pituitary Gland
Fulltext Endocrinological Outcome of Endoscopic Transsphenoidal Surgery for Functioning and Non-Functioning Pituitary Adenoma

Yi LS, Alias A, Ghani ARI, Bidin MBL

Malays J Med Sci, 2019 May;26(3):64-71.
PMID: 31303851 MyJurnal DOI: 10.21315/mjms2019.26.3.5

Introduction: The present study analysed the (i) remission and preservation of hormones, (ii) endocrinological and anatomical complications and (iii) visual improvement after endoscopic transsphenoidal surgery (ETS).
Methods: The retrospective observational study of all consecutive cases of pituitary adenoma treated with ETS in Hospital Kuala Lumpur (HKL) between 2006 and 2015. Age, sex, pre- and post-operative hormone level, tumour size, and complications were noted.
Results: A total of 67 patients were diagnosed with non-functioning pituitary adenoma throughout this period. Of these, 11 patients had both visual and hormonal improvement post-operation. Of the 27 patients with tumour invaded into the cavernous sinus, 13 showed an improved vision. In the adenoma patients who had impaired hormonal function before the surgery, the hormone level normalised post-surgery in 42 patients. Moreover, 39 patients were diagnosed with functioning pituitary adenoma. Ten patients recovered from acromegaly and four patients recovered from Cushing disease within seven days post-operative. Also, five patients with functioning adenoma suffered complications.
Conclusion: Outcome for the preservation and hormone recovery in non-functioning pituitary adenoma group was satisfactory, with only one patient's hormonal level worsening. No visual deterioration and mortality were detected throughout this study. A dedicated team specialised in endoscopic transsphenoidal pituitary surgery further improved the outcome of this surgical method.

Matched MeSH terms: Pituitary Gland
Molecular, cellular, morphological, physiological and behavioral aspects of gonadotropin-inhibitory hormone

Ubuka T, Son YL, Tsutsui K

Gen Comp Endocrinol, 2016 Feb 1;227:27-50.
PMID: 26409890 DOI: 10.1016/j.ygcen.2015.09.009

Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic neuropeptide that was isolated from the brains of Japanese quail in 2000, which inhibited luteinizing hormone release from the anterior pituitary gland. Here, we summarize the following fifteen years of researches that investigated on the mechanism of GnIH actions at molecular, cellular, morphological, physiological, and behavioral levels. The unique molecular structure of GnIH peptide is in its LPXRFamide (X=L or Q) motif at its C-terminal. The primary receptor for GnIH is GPR147. The cell signaling pathway triggered by GnIH is initiated by inhibiting adenylate cyclase and decreasing cAMP production in the target cell. GnIH neurons regulate not only gonadotropin synthesis and release in the pituitary, but also regulate various neurons in the brain, such as GnRH1, GnRH2, dopamine, POMC, NPY, orexin, MCH, CRH, oxytocin, and kisspeptin neurons. GnIH and GPR147 are also expressed in gonads and they may regulate steroidogenesis and germ cell maturation in an autocrine/paracrine manner. GnIH regulates reproductive development and activity. In female mammals, GnIH may regulate estrous or menstrual cycle. GnIH is also involved in the regulation of seasonal reproduction, but GnIH may finely tune reproductive activities in the breeding seasons. It is involved in stress responses not only in the brain but also in gonads. GnIH may inhibit male socio-sexual behavior by stimulating the activity of cytochrome P450 aromatase in the brain and stimulates feeding behavior by modulating the activities of hypothalamic and central amygdala neurons.

Matched MeSH terms: Pituitary Gland/metabolism*
Immunohistochemical characteristics of the hypophysis in normal conditions and chronic stress

Kapitonova MY, Kuznetsov SL, Khlebnikov VV, Zagrebin VL, Morozova ZCh, Degtyar YV

Neurosci. Behav. Physiol., 2010 Jan;40(1):97-102.
PMID: 20012496 DOI: 10.1007/s11055-009-9217-4

Quantitative immunohistochemical methods were used to assess activation of the hypothalamo-hypophyseal-adrenocortical system at the level of its central component - the adenohypophysis - in the growing body during chronic exposure to psychoemotional stressors of different strengths. Sprague-Dawley rats aged 30 days were subjected to "mild" or "severe" immobilization stress for 5 h per day for seven days. Animals were decapitated at the end of the last stress session and the endocrine glands (hypophysis, adrenals) were harvested, weighed, and embedded in paraffin; sections were stained with hematoxylin and eosin, and also immunohistochemically using monoclonal antibodies to adrenocorticotropic hormone (ACTH) and proliferating cell nuclear antigen (PCNA) following by automated image analysis. These studies showed that stress-associated hyperplasia of corticotropocytes in rats of pubertal age was due more to the differentiation of existing immature precursor cells than to cell proliferation.

Matched MeSH terms: Pituitary Gland/metabolism*; Pituitary Gland/pathology
Differential effect of adrenocorticosteroids on 11 beta-hydroxysteroid dehydrogenase bioactivity at the anterior pituitary and hypothalamus in rats

Idrus RB, Mohamad NB, Morat PB, Saim A, Abdul Kadir KB

Steroids, 1996 Aug;61(8):448-52.
PMID: 8870163

11 beta-Hydroxysteroid dehydrogenase (11 beta-OHSD) is a microsomal enzyme that catalyzes the dehydrogenation of cortisol (F) to cortisone (E) in man and corticosterone (B) to 11-dehydrocorticosterone (A) in rats. 11 beta-OHSD has been identified in a wide variety of tissues. The differential distribution of 11 beta-OHSD suggests that this enzyme has locally defined functions that vary from region to region. The aim of this study was to investigate the effects of the glucocorticoids B and dexamethasone (DM), the mineralocorticoid deoxycorticosterone (DOC), and the inhibitors of 11 beta-OHSD glycyrrhizic acid (Gl) and glycyrrhetinic acid (GE) on 11 beta-OHSD bioactivity at the hypothalamus (HT) and anterior pituitary (AP). Male Wistar rats were treated with GI or were adrenalectomized (ADX) and treated with either B, DM, or DOC for 7 days. All treatments were in vivo except GE, which was used in vitro. At the end of treatment, homogenates of HT and AP were assayed for 11 beta-OHSD bioactivity, expressed as the percentage conversion of B to A in the presence of NADP, 11 beta-OHSD bioactivity is significantly higher (P < 0.0001) in the AP compared with the HT. Adrenalectomy significantly increased the enzyme activity in the AP (P < 0.05), an effect reversed by B or DM. ADX rats treated with DOC showed decreased enzyme activity in the AP (P < 0.001) but increased the activity in the HT (P < 0.0001). Gl increased activity in both HT and AP, whereas GE decreased activity significantly. We conclude that the modulation of 11 beta-OHSD is both steroid specific and tissue specific.

Matched MeSH terms: Pituitary Gland, Anterior/drug effects; Pituitary Gland, Anterior/enzymology*
GnRH and gpcr: laser-captured single cell gene profiling

Parhar IS

Fish Physiol Biochem, 2005 Apr;31(2-3):153-6.
PMID: 20035450 DOI: 10.1007/s10695-006-0018-1

We have developed a novel single cell real-time quantitative PCR technique, which incorporates harvesting marker-identified single cells using laser-capture. Here, for the first time in a vertebrate species, using this innovative single cell gene profiling technique, we report the presence of G-protein coupled receptors in individual gonadotropin-releasing hormone (GnRH) neurons and endocrine cells of the pituitary of the tilapia Oreochromis niloticus. The differential expression of multiple combinations of three GnRH receptor types (R1, R2 and R3) in individual gonadotropic and nongonadotropic cells demonstrates cellular and functional heterogeneity. The differential use of GnRH receptors in corticotropes, melanotropes and thyrotropes during gonadal maturation and reproductive behaviors suggests new roles for these hormones. Further, we provide evidence of the structure of a novel nonmammalian G-protein coupled receptor (GPR54) for kisspeptins, encoded by Kiss-1 gene, which is highly conserved during evolution and expressed in GnRH1, GnRH2 and GnRH3 neurons. We hypothesize GPR54 stimulates GnRH secretion and is crucial for pubertal maturation. We speculate, the use of this method will allow the identification and quantification of known and unknown genes in single cells, which would greatly facilitate our understanding of the complex interactions that govern the physiology of individual cells in vertebrates species.

Matched MeSH terms: Pituitary Gland

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