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  1. Wong JSL, Nasruddin AB, Selveindran NM, Latif KA, Kassim F, Nair SB, et al.
    AACE Clin Case Rep, 2021 02 01;7(3):220-225.
    PMID: 34095493 DOI: 10.1016/j.aace.2021.01.008
    Objective: Primary hypophysitis refers to the isolated inflammation of the pituitary gland not associated with other secondary causes. Among its histopathologic subtypes, xanthomatous is the rarest.

    Methods: We describe a 22-year-old woman with xanthomatous hypophysitis (XH), its clinical progression over 8 years as well as the treatment effects of prednisolone and azathioprine. Our patient was first referred for severe short stature and delayed puberty at the age of 14 years.

    Results: Investigations revealed multiple pituitary deficiencies. Magnetic resonance imaging showed a pituitary mass whereby a partial resection was performed. A full resection was not feasible due to the location of the mass. The histopathologic analysis of the tissue was consistent with XH. The results of secondary workout for neoplasm, infection, autoimmune, and inflammatory disorders were negative. After surgery, a progressive enlargement of the mass was observed. Two courses of prednisolone were administered with a significant reduction in the mass size. Azathioprine was added due to the unsustained effects of prednisolone when tapered off and the concern of steroid toxicity with continued use. No further increase in the mass size was noted after 6 months on azathioprine.

    Conclusion: Glucocorticoid and immunotherapy are treatment options for XH; however, more cases are needed to better understand its pathogenesis and clinical progression.

    Matched MeSH terms: Pituitary Gland
  2. Chung WH, Chiu CK, Wei Chan CY, Kwan MK
    Acta Orthop Traumatol Turc, 2020 Sep;54(5):561-564.
    PMID: 33155569 DOI: 10.5152/j.aott.2020.19144
    Growth hormone secreting pituitary tumor or gigantism has not been previously reported to be associated with rapid progression of scoliosis in the literature. However, there are some reports indicating scoliosis can be worsened by growth hormone therapy in children and adolescents. A 19-year-old boy was referred to our institution for the treatment of a right thoracolumbar scoliosis. The Cobb angle had worsened from 29° to 83° over two years' duration. He attained puberty at the age of 13. He had a previous history of slipped upper femoral epiphysis (SUFE), which was operated in 2015, with no clinical features of gigantism. Preoperative assessment was performed. He was diagnosed with growth hormone secreting pituitary macroadenoma by magnetic resonance imaging with a high serum level of insulin-like growth factor-I (IGF-I). Computed tomography (CT) of the pancreas showed a pancreatic endocrine tumor. The patient was later diagnosed with multiple endocrine neoplasia type 1 (MEN 1). He underwent endoscopic endonasal excision of the pituitary mass and distal pancreatectomy. This case indicates that growth hormone secreting pituitary macroadenoma could result in rapid progression of scoliosis.
    Matched MeSH terms: Pituitary Gland/surgery
  3. 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
  4. Jesse FF, Ibrahim HH, Abba Y, Chung EL, Marza AD, Mazlan M, et al.
    BMC Vet Res, 2017 Apr 05;13(1):88.
    PMID: 28381248 DOI: 10.1186/s12917-017-1010-y
    BACKGROUND: Hemorrhagic septicemia is a fatal disease of cattle and buffaloes caused by P. multocida. Although the pathogenesis of the bacteria has been well established in literature, there is a paucity of information on the possible role of the bacteria and its immunogens; lipopolysaccharide (LPS) and outer membrane proteins (OMPs) on the reproductive capacity of buffalo heifers.

    METHODS: In this study, twenty one healthy prepubertal female buffaloes aged 8 months were divided into seven groups of 3 buffaloes each (G1-G7). Group 1 (G1) served as the negative control group and were inoculated orally with 10 mL sterile Phosphate Buffer Saline (PBS), groups 2 (G2) and 3 (G3) were inoculated orally and subcutaneously with 10 mL of 10(12) colony forming unit (cfu) of P.multocida type B: 2, while groups 4 (G4) and 5 (G5) received 10 mL of bacterial LPS orally and intravenously, respectively. Lastly, groups 6 (G6) and 7 (G7) were orally and subcutaneously inoculated with 10 mL of bacterial OMPs. Whole blood was collected in EDTA vials at stipulated time points (0, 2, 4, 6, 8, 10, 12, 24, 36, 48, 72, 120, 168, 216, 264, 312, 360, 408, 456 and 504 h), while tissue sections of the pituitary glands were collected and transported to the histopathology laboratory in 10% buffered formalin for processing and Hematoxylin and eosin staining. Plasma levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), progesterone (PG), estradiol (EST) and gonadotrophin releasing hormone (GnRH) were determined.

    RESULTS: The histopathological lesions observed in the pituitary gland included hemorrhage, congestion, inflammatory cell infiltration, hydropic degeneration, necrosis and edema. These changes were higher (p 

    Matched MeSH terms: Pituitary Gland/pathology
  5. Wan Muhamad Hatta SF, Hamdan MF, Md Ali SA, Abdul Ghani R
    BMJ Case Rep, 2016 Sep 09;2016.
    PMID: 27613264 DOI: 10.1136/bcr-2016-216395
    Idiopathic granulomatous hypophysitis (GH) is an uncommon inflammatory disease of the pituitary with impairment of pituitary gland function due to infiltration by lymphocytes, plasma cells and macrophages. We report the case of a 39-year-old woman who presented with worsening of headaches for 1 month and blurring of vision over 5 days. An MRI revealed a homogeneous supra-sellar mass evoking a pituitary tumour with bulky pituitary stalk extending into the left and right cavernous sinuses. Hormonal investigations showed anterior pituitary hormone deficiencies; meanwhile histopathological examination revealed an aspect of hypophysitis. Clinical and radiological remission occurred immediately postglucocorticoid therapy with the addition of a steroid-sparing agent later in view of recurrence of symptoms on glucocorticoid dose reduction. GH has important diagnostic and therapeutic implications, as clinical and radiological features ameliorate via medical treatment. With further understanding and recognition of the disease, we hope to highlight a case of GH, in which signs and symptoms improved after initiation of corticosteroids.
    Matched MeSH terms: Pituitary Gland/pathology*
  6. Ng KY, Leong MK, Liang H, Paxinos G
    Brain Struct Funct, 2017 Sep;222(7):2921-2939.
    PMID: 28478550 DOI: 10.1007/s00429-017-1439-6
    Melatonin, through its different receptors, has pleiotropic functions in mammalian brain. Melatonin is secreted mainly by the pineal gland and exerts its effects via receptor-mediated and non-receptor-mediated actions. With recent advancement in neuroanatomical mapping, we may now understand better the localizations of the two G protein-coupled melatonin receptors MT1 and MT2. The abundance of these melatonin receptors in respective brain regions suggests that receptor-mediated actions of melatonin might play crucial roles in the functions of central nervous system. Hence, this review aims to summarize the distribution of melatonin receptors in the brain and to discuss the putative functions of melatonin in the retina, cerebral cortex, reticular thalamic nucleus, habenula, hypothalamus, pituitary gland, periaqueductal gray, dorsal raphe nucleus, midbrain and cerebellum. Studies on melatonin receptors in the brain are important because cumulative evidence has pointed out that melatonin receptors not only play important physiological roles in sleep, anxiety, pain and circadian rhythm, but might also be involved in the pathogenesis of a number of neurodegenerative diseases including Alzheimer's disease, Parkinson's disease and Huntington's disease.
    Matched MeSH terms: Pituitary Gland
  7. Ogawa S, Sivalingam M, Anthonysamy R, Parhar IS
    Cell Tissue Res, 2020 Feb;379(2):349-372.
    PMID: 31471710 DOI: 10.1007/s00441-019-03089-5
    Kisspeptin is a hypothalamic neuropeptide, which acts directly on gonadotropin-releasing hormone (GnRH)-secreting neurons via its cognate receptor (GPR54 or Kiss-R) to stimulate GnRH secretion in mammals. In non-mammalian vertebrates, there are multiple kisspeptins (Kiss1 and Kiss2) and Kiss-R types. Recent gene knockout studies have demonstrated that fish kisspeptin systems are not essential in the regulation of reproduction. Studying the detailed distribution of kisspeptin receptor in the brain and pituitary is important for understanding the multiple action sites and potential functions of the kisspeptin system. In the present study, we generated a specific antibody against zebrafish Kiss2-R (=Kiss1Ra/GPR54-1/Kiss-R2/KissR3) and examined its distribution in the brain and pituitary. Kiss2-R-immunoreactive cell bodies are widely distributed in the brain including in the dorsal telencephalon, preoptic area, hypothalamus, optic tectum, and in the hindbrain regions. Double-labeling showed that not all but a subset of preoptic GnRH3 neurons expresses Kiss2-R, while Kiss2-R is expressed in most of the olfactory GnRH3 neurons. In the posterior preoptic region, Kiss2-R immunoreactivity was seen in vasotocin cells. In the pituitary, Kiss2-R immunoreactivity was seen in corticotropes, but not in gonadotropes. The results in this study suggest that Kiss2 and Kiss2-R signaling directly serve non-reproductive functions and indirectly subserve reproductive functions in teleosts.
    Matched MeSH terms: Pituitary Gland/metabolism
  8. Ogawa S, Liu X, Shepherd BS, Parhar IS
    Cell Tissue Res, 2018 Nov;374(2):349-365.
    PMID: 29934855 DOI: 10.1007/s00441-018-2870-6
    Ghrelin, a gut-brain peptide hormone, is implicated in a multiplicity of biological functions, including energy homeostasis and reproduction. Neuronal systems that are involved in energy homeostasis as well as reproduction traverse the hypothalamus; however, the mechanism by which they control energy homeostasis is not fully understood. The present study analyzes the anatomical relationship of neurons expressing gonadotropin-releasing hormone (GnRH), neuropeptide Y (NPY) and growth hormone-releasing hormone (GHRH) in a cichlid, tilapia (Oreochromis niloticus). Additionally, we examine in vivo effects of ghrelin on these hypothalamic neurons and plasma growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels. Double-immunofluorescence showed neuronal fiber associations between GnRH, NPY and GHRH in the brain and pituitary. Intracerebroventricular injection of ghrelin had no effect on numbers, soma size, or optical density of GnRH and NPY neurons, whereas the number of GHRH neurons was significantly decreased in the animals injected with ghrelin when compared to controls, which may indicate administered ghrelin promoted GHRH release. Plasma GH and pituitary GH mRNA levels were significantly increased in the animals injected with ghrelin. These results suggest that central administration of ghrelin primarily act on hypothalamic GHRH neurons to stimulate GH release from the pituitary in the tilapia.
    Matched MeSH terms: Pituitary Gland
  9. 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
  10. Biran J, Golan M, Mizrahi N, Ogawa S, Parhar IS, Levavi-Sivan B
    Endocrinology, 2014 Dec;155(12):4831-42.
    PMID: 25211586 DOI: 10.1210/en.2013-2114
    Neurokinin B (NKB) was recently identified as a key regulator of reproduction in mammals and fish. Fish were found to possess a specific novel neurokinin termed NKF. To study the role of NKB/NKF in the regulation of fish reproduction and to investigate the role of NKB/NKF and their receptors in the piscine pituitary, we have identified the NKB/tachikinin 3 receptor (tac3r) system in tilapia. Bioinformatics and phylogenetic analyses have demonstrated that the tilapia holds 1 putative tac3 gene and 2 NKB receptor genes (tac3ra and tac3rb) that clustered with other piscine Tac3 and NKB receptor lineages. Furthermore, we found that in African cichlids, NKB peptides differ from other vertebrate NKBs in their C-terminal sequence, possessing isoleucine instead of valine as the X in the NKB FXGLM-NH2-terminal consensus sequence. Signal transduction analysis demonstrated that tilapia NKB (tiNKB), tiNKF, and human NKB activated both CRE-luc and SRE-luc transcriptional activity of both tilapia and human NKB receptors. Two hours after ip injection of tiNKB, the plasma levels of both FSH and LH were increased, whereas tiNKF was more effective in increasing LH levels. However, tiNKB was more effective than tiNKF in increasing both FSH and LH from tilapia pituitary dispersed cells. Using in situ hybridization and fluorescent immunohistochemistry, we have shown that LH cells possess tac3, tac3ra, and tac3rb mRNAs, whereas FSH cells possess mainly tac3rb and tac3ra and tac3 to a much lesser extent. These results suggest that the members of the NKB/tac3r system may serve as paracrine/autocrine regulators of gonadotropin release in fish pituitary.
    Matched MeSH terms: Pituitary Gland/metabolism*
  11. Kitahashi T, Ogawa S, Soga T, Sakuma Y, Parhar I
    Endocrinology, 2007 Dec;148(12):5822-30.
    PMID: 17823257
    The role of steroid/thyroid hormones in the regulation of endocrine cells at the level of the pituitary has remained unclear. Therefore, using single-cell quantitative real-time PCR, we examined absolute amounts of transcripts for nuclear receptors [estrogen receptors (ERs) alpha, beta, and gamma; androgen receptors (ARs) a and b; glucocorticoid receptors (GRs) 1, 2a, and 2b; and thyroid hormone receptors (TRs) alpha1, alpha2, and beta] in pituitary cells of immature (IM) and mature (M) male tilapia, Oreochromis niloticus. In the two reproductive stages, ACTH cells expressed only ERbeta, whereas all other pituitary cell types expressed ERalpha + beta, and a subpopulation coexpressed ARa, ARb, GR1, GR2b, and TRbeta but lacked ERgamma, GR2a, TRalpha1, and TRalpha2. IM males had high percentages of LH cells (IM 46.0% vs. M 10.0%), GH cells (IM 23.3% vs. M 7.9%), and prolactin cells (IM 68.8% vs. M 6.0%) with ERbeta, and TSH cells (IM 19.2% vs. M 0.0%) and MSH cells (IM 25.6% vs. M 0.0%) with ERalpha + TRbeta. A high percentage of FSH cells in IM males expressed ERbeta (IM 46.9% vs. M 18.8%), and FSH cells in M males showed significantly high GR1 transcripts (IM 76.0 +/- 5.0 vs. M 195.0 +/- 10.7 copies per cell; P < 0.05), suggesting that FSH cells are regulated differently in the two reproductive stages. Coexpression of ERalpha + beta in high percentages of cells of the GH family (GH, IM 43.8% vs. M 14.3%; prolactin, IM 8.3% vs. M 59.7%; somatolactin, IM 22.2% vs. M 42.2%) suggests that the expression of both ERs is important for functionality. Thus, differential coexpression of genes for nuclear receptors in subpopulations of pituitary cell types suggests multiple steroid/thyroid hormone regulatory pathways at the level of the pituitary during the two reproductive stages.
    Matched MeSH terms: Pituitary Gland/cytology; Pituitary Gland/metabolism*
  12. Abdullah NRA, Jason WLC, Nasruddin AB
    PMID: 28567291 DOI: 10.1530/EDM-17-0029
    Pachydermoperiostosis is a very rare osteoarthrodermopathic disorder whose clinical and radiographic presentations may mimic those of acromegaly. In the evaluation of patients with acromegaloid appearances, pachydermoperiostosis should be considered as a differential diagnosis. In this article, we report a 17-year-old boy who presented with 2-year history of acral enlargement and facial appearance changes associated with joint pain and excessive sweating. He had been investigated extensively for acromegaly, and the final diagnosis was pachydermoperiostosis.

    LEARNING POINTS: There is a broad range of differential diagnosis for acromegaloid features such as acromegaly, pseudoacromegaly with severe insulin resistance, Marfan's syndrome, McCune-Albright and a rare condition called pachydermoperiostosis.Once a patient is suspected to have acromegaly, the first step is biochemical testing to confirm the clinical diagnosis, followed by radiologic testing to determine the cause of the excess growth hormone (GH) secretion. The cause is a somatotroph adenoma of the pituitary in over 95 percent of cases.The first step is measurement of a serum insulin-like growth factor 1 (IGF1). A normal serum IGF1 concentration is strong evidence that the patient does not have acromegaly.If the serum IGF1 concentration is high (or equivocal), serum GH should be measured after oral glucose administration. Inadequate suppression of GH after a glucose load confirms the diagnosis of acromegaly.Once the presence of excess GH secretion is confirmed, the next step is pituitary magnetic resonance imaging (MRI).Atypical presentation warrants revision of the diagnosis. This patient presented with clubbing with no gigantism, which is expected in adolescent acromegalics as the growth spurt and epiphyseal plate closure have not taken place yet.

    Matched MeSH terms: Pituitary Gland
  13. 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
  14. Tsutsui K, Ubuka T, Son YL, Bentley GE, Kriegsfeld LJ
    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
  15. Ogawa S, Parhar IS
    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
  16. Parhar IS, Ogawa S, Ubuka T
    PMID: 27065948 DOI: 10.3389/fendo.2016.00028
    Social behaviors are key components of reproduction, because they are essential for successful fertilization. Social behaviors, such as courtship, mating, and aggression, are strongly associated with sex steroids, such as testosterone, estradiol, and progesterone. Secretion of sex steroids from the gonads is regulated by the hypothalamus-pituitary-gonadal (HPG) axis in vertebrates. Gonadotropin-releasing hormone (GnRH) is a pivotal hypothalamic neuropeptide that stimulates gonadotropin release from the pituitary. In recent years, the role of neuropeptides containing the C-terminal Arg-Phe-NH2 (RFamide peptides) has been emphasized in vertebrate reproduction. In particular, two key RFamide peptides, kisspeptin and gonadotropin-inhibitory hormone (GnIH), emerged as critical accelerator and suppressor of gonadotropin secretion. Kisspeptin stimulates GnRH release by directly acting on GnRH neurons, whereas GnIH inhibits gonadotropin release by inhibiting kisspeptin, GnRH neurons, or pituitary gonadotropes. These neuropeptides can regulate social behavior by regulating the HPG axis. However, distribution of neuronal fibers of GnRH, kisspeptin, and GnIH neurons is not limited within the hypothalamus, and the existence of extrahypothalamic neuronal fibers suggests direct control of social behavior within the brain. It has traditionally been shown that central administration of GnRH can stimulate female sexual behavior in rats. Recently, it was shown that Kiss1, one of the paralogs of kisspeptin peptide family, regulates fear responses in zebrafish and GnIH inhibits sociosexual behavior in birds. Here, we highlight recent findings regarding the role of GnRH, kisspeptin, and GnIH in the regulation of social behaviors in fish, birds, and mammals and discuss their importance in future biological and biomedical research.
    Matched MeSH terms: Pituitary Gland
  17. Mizrahi N, Gilon C, Atre I, Ogawa S, Parhar IS, Levavi-Sivan B
    PMID: 31354632 DOI: 10.3389/fendo.2019.00469
    Neurokinin B (NKB) and its cognate receptor (NK3R) are emerging as important components of the neuroendocrine regulation of reproduction. Unlike mammalian tac3, which encodes only one mature peptide (namely NKB), two mature peptides are predicted for each tac3 gene in fish and frogs. Therefore, it was designated as Neurokinin F (NKF). Hormone analogs with high and long-lasting biological activity are important tools for physiological and biological research; however, the availability of piscine-specific analogs is very limited. Therefore, we have developed specific NKB and NKF analogs based on the structure of the mammalian NKB analog-senktide. These analogs, specifically designed for longer half-lives by methylation of proteolysis sites, exhibited activity equal to those of the native NKB and NKF in short-term signal-transduction assays of tilapia NKB receptors. However, the analogs were found to be able to significantly increase the release of luteinizing hormone (LH), follicle stimulating hormone (FSH) and growth hormone (GH) in tilapia, as fast as 1 h after intraperitoneal (IP) injection. The impact of the analogs on LH and FSH secretion lasted longer compared to the effect of native peptides and salmon GnRH analog (sGnRHa). In addition, we harvested pituitaries 24 h post injection and measured LH, FSH and GH mRNA synthesis. Both analogs elevated mRNA levels of LH and GH, but only NKB analog increased FSH mRNA levels in the pituitary and all GnRH forms in the brain. NKB receptors were co-localized with all three types the GnRH neurons in tilapia brain in situ. We previously showed a direct effect of NKB at the pituitary level, and these new results suggest that the stronger impact of the NKB analog on GTH release is also due to an indirect effect through the activation of GnRH neurons. These results suggest that novel synthetic NKB analogs may serve as a tool for both research and agricultural purposes. Finally, the biological activity and regulatory role of NKB in tilapia brain and pituitary suggest that the NKB/NKBR system in fish is an important reproductive regulator in a similar way to the kisspeptin system in mammals.
    Matched MeSH terms: Pituitary Gland
  18. 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*
  19. Maneesh M, Dutta S, Chakrabarti A, Vasudevan DM
    Indian J. Physiol. Pharmacol., 2006 Jul-Sep;50(3):291-6.
    PMID: 17193902
    Ethanol is a testicular toxin and it causes fertility abnormalities with low sperm count and impaired sperm motility in men. The present study was designed to investigate plasma testosterone level and hypothalamic pituitary gonadal (HPG) axis function in alcoholic men and also effect of ethanol on systemic oxidative stress. Forty six male alcohol abusers in the age group 20-40 years were selected. Fifty five, males in the same age group served as control. Alcohol abusers had significantly low plasma testosterone with low luteinizing hormone and follicle stimulating hormone. In addition they had significantly high thiobarbituric acid reactive substances (TBARS), superoxide dismutase and glutathione S-transferase, and low glutathione, ascorbic acid, catalase, glutathione reductase and glutathione peroxidase. Moreover, serum testosterone level in alcoholics negatively correlated with duration of alcohol abuse, and TBARS. Duration dependent decreased serum testosterone level in alcohol abusers might be due to 1) increased oxidative stress which can damage Leydig and supporting Sertoli cells and 2) impaired HPG axis.
    Matched MeSH terms: Pituitary Gland/metabolism
  20. Elyasi Gorji Z, Amiri-Yekta A, Gourabi H, Hassani S, Fatemi N, Zerehdaran S, et al.
    Iran J Biotechnol, 2015 Jun;13(2):10-17.
    PMID: 28959285 DOI: 10.15171/ijb.1004
    BACKGROUND: Follicle stimulating hormone (FSH) plays an essential role in reproductive physiology and follicular development.

    OBJECTIVE: A new variant of the equine fsh (efsh) gene was cloned, sequenced, and expressed in Pichia pastoris (P. pastoris) GS115 yeast expression system.

    MATERIALS AND METHODS: The full-length cDNAs of the efshα and efshβ chains were amplified by reverse transcription polymerase chain reaction (RT-PCR) using the total RNA isolated from an Iranian Turkmen-thoroughbred horse's anterior pituitary gland. The amplified efsh chains were cloned into the pPIC9 vector and transferred into P. pastoris. The secretion of recombined eFSH using P. pastoris expression system was confirmed by Western blotting and immunoprecipitation (IP) methods.

    RESULTS: The DNA sequence of the efshβ chain accession number JX861871, predicted two putative differential nucleotide arrays, both of which are located in the 3'UTR. Western blotting showed a molecular mass of 13 and 18 kDa for eFSHα and eFSHβ subunits, respectively. The expression of desired protein was confirmed by protein G immunoprecipitation kit.

    CONCLUSIONS: eFSH successfully expressed in P. pastoris. These findings lay a foundation to improve ovulation and embryo recovery rates as well as the efficiency of total embryo-transfer process in mares.

    Matched MeSH terms: Pituitary Gland, Anterior
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