• Title/Summary/Keyword: Anterior pituitary

Search Result 54, Processing Time 0.027 seconds

The Consequences of Mutations in the Reproductive Endocrine System

  • Choi, Donchan
    • Development and Reproduction
    • /
    • v.16 no.4
    • /
    • pp.235-251
    • /
    • 2012
  • The reproductive activity in male mammals is well known to be regulated by the hypothalamus-pituitary-gonad axis. The hypothalamic neurons secreting gonadotropin releasing hormone (GnRH) govern the reproductive neuroendocrine system by integrating all the exogenous information impinging on themselves. The GnRH synthesized and released from the hypothalamus arrives at the anterior pituitary through the portal vessels, provoking the production of the gonadotropins(follicle-stimulating hormone (FSH) and luteinizing hormone (LH)) at the same time. The gonadotropins affect the gonads to promote spermatogenesis and to secret testosterone. Testosterone acts on the GnRH neurons by a feedback loop through the circulatory system, resulting in the balance of all the hormones by regulating reproductive activities. These hormones exert their effects by acting on their own receptors, which are included in the signal transduction pathways as well. Unexpected aberrants are arised during this course of action of each hormone. This review summarizes these abnormal phenomena, including various mutations of molecules and their actions related to the reproductive function.

Progesterone Inhibits Luteinizins Hormone $\beta$ Subunit (LHP) Gene Expression in the Rat Pituitary in a Svnergic Manner (프로제스테론은 흰쥐 뇌하수체에서 LH$\beta$유전 발현을 에스트로젠과 상승작용으로 억제한다.)

  • 조병남;성재영
    • The Korean Journal of Zoology
    • /
    • v.37 no.3
    • /
    • pp.377-384
    • /
    • 1994
  • The present study examines the inhibitow effect of progesterone (P) on luteinizing hormone $(LH)\beta$ subunit gene expression in anterior pituitary of ovariectomized, estradiol-treated adult rats. A single injection of P (1mg) further decreased the estradiol-Induced decrease in $LH\beta$ mRNA levels in ovariectomTzed rats in a time-dependent manner. p suppressed UIP mRNA levels at lower doses (0.1 and 1mg), but increased $LH\beta$ mRNA levels 81 a high dose (toms). The inhibitor action of P on $Uf\beta$ mRNA was restored when Ru486, a P receptor antagonist, was administered 1h before P treatment. These data clearly indicate that P inhibits gene expression of $LH\beta$ in the rift pituitary in a swersic manner with estrogen.

  • PDF

Silent Adenomas of Pituitary Gland : It's Immunohistochemical Features and Clinical Characteristics

  • Shim, Jae-Hyone;Song, Young-Jin;Kim, Dae-Chul;Park, Mi-Kyung;Choi, Sun-Seob;Kim, Ki-Uk
    • Journal of Korean Neurosurgical Society
    • /
    • v.40 no.5
    • /
    • pp.330-335
    • /
    • 2006
  • Objective : The aim of the study was to review the clinical and radiological findings of those non-functioning adenomas[NFAs] with positive immnoreactivity for anterior pituitary hormones. Methods : Sixty patients with pituitary adenoma were treated at the author's institution between January 2000 and July 2005. All consecutive patients were underwent transsphenoidal surgery by same operator. In addition to the routine histopathological examination, surgical specimen was examined by immunohistochemical staining against adenohypophyseal cells. And clinical analysis was performed by retrospective review of medical records, neuroimaging examinations and immunohistochemical technique. We classified these pituitary adenomas into functioning adenomas [group F], immuno-positive NFAs [group S, so-called silent adenoma] and immuno-negative NFAs [group N], and compared clinical and radiological differences between group F, N, and S. Results : Of the 60 cases, group F was 25, group S was 25, and group N was 10. Among the group S, 5 cases showed reactivity against PRL, 1 against GH, 1 against both PRL and GH, 1 against TSH and GH, 2 against ACTH, 11 against FSH and 4 against both LH and FSH. Radiologically, invasiveness was noted in 8 in group S, compared to 3 in group N and 1 in group F [p = 0.02]. Intratumoral bleeding was noted in 7 of group S, 2 of group N and 2 of group F [p >0.05]. Conclusion : Silent adenomas were thought to behave more aggressive than other subgroups of pituitary adenomas. And so we suggest the immunohistochemical study against adenohypophyseal cells may be helpful for evaluating clinical course of pituitary adenoma, expecially for, NFAs.

Expression of pituitary adenylate cyclase activating polypeptide in the adult rat testis by in situ hybridization and immunohistochemistry (In situ hybridization법과 면역조직화학적법을 이용한 성숙한 흰쥐고환에서의 pituitary adenylate cyclase activating polypeptide의 발현)

  • Koh, Phil-ok;Kwak, Soo-dong
    • Korean Journal of Veterinary Research
    • /
    • v.41 no.1
    • /
    • pp.1-6
    • /
    • 2001
  • Pituitary adenyl ate cyclase activating polypeptide (PACAP) was originally isolated from the ovine hypothalamus and stimulated cAMP production in anterior pituitary cells. It is known that PACAP stimulates cAMP accumulation and contributes to the spermatogenesis and steroidogenesis in rat testis. The principal aim of this study is to determinate the distribution of PACAP mRNA and protein in adult rat testis. For this study, we used in situ hybridization and immunohistochemistry techniques in adult rat testis. PACAP mRNA was stage specifically expressed in seminiferous tubules. Positive signals of PACAP mRNA were detected in the developing germ cells at stages HI-VII of the epithelial cycle. The strongest signals of PACAP mRNA and protein were detected in round spermatids at stages V to early VII of the cycle. These results demonstrate that PACAP which is synthesised in the developing germ cells contributes to the spermatogenesis in rat testis. Thus, we suggest that PACAP plays a critical role in the function of testis.

  • PDF

New Landmark for the Endoscopic Endonasal Transsphenoidal Approach of Pituitary Surgery

  • Kim, Young Ha;Kim, Ju Eun;Kim, Min Joo;Cho, Jin Hee
    • Journal of Korean Neurosurgical Society
    • /
    • v.53 no.4
    • /
    • pp.218-222
    • /
    • 2013
  • Objective : To clarify the anatomical correlations of the sphenoid sinus with surrounding structures in the normal Korean population, and to identify surgical landmarks for safe sellar floor dissection in the anterior skull base by endoscopy and microscopy. Methods : We reviewed the 196 brain magnetic resonance imaging findings showing a normal appearance, and measured the distances between anatomical landmarks. Results : The mean distances from the base of the columella to the anterior wall of the sphenoid sinus and the sellar floor were $69.71{\pm}4.25$ mm and $86.26{\pm}4.57$ mm, respectively in the over 15 age group, and showed the smallest degree of variation among the measurements. The mean angles between the floor of the nasal cavity and the straight line connecting the base of the columella and the sellar floor were $29.45{\pm}3.25^{\circ}$ and $24.75{\pm}4.00^{\circ}$ in the over 15 and under 15 age groups, respectively. The mean values of both distances and angles increased with age until 15 years after which no further increases were evident. There were no significant differences in the measurements between males and females or among subjects with different degrees of pneumatization in the over 15 age group. Conclusion : The distances from the base of the columella to the sellar floor and the anterior wall of the sphenoid sinus, which were consistent among individuals, could be used as a surgical indicator to investigate the sellar floor in endoscopic or microscopic transsphenoidal approaches.

Effect of Ultramarathon on the Anterior Pituitary and Thyroid Hormones (울트라마라톤이 뇌하수체 전엽 및 갑상선 호르몬에 미치는 영향)

  • Shin, Kyung-A;Kim, Young-Joo
    • The Korean journal of sports medicine
    • /
    • v.36 no.4
    • /
    • pp.214-220
    • /
    • 2018
  • Purpose: The purpose of this research is to study changes in pituitary hormone in anterior lobe and thyroid hormone before, after, and during recovery time in severe 100 km ultramarathon. Methods: Healthy middle-aged runners (age, $52.0{\pm}4.8$ years) participated in the test. Grade exercise test is done, and then blood is taken from those participants before and after completing 100 km ultramarathon at the intervals of 24 hours (1 day), 72 hours (3 days), and 120 hours (5 days) to analyze their luteinizing hormone (LH), follicle-stimulating hormone (FSH), thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), and free thyroxine (Free T4). Results: For LH, it decreased more significantly at 100 km than pre-race. However, after 1 day result increased more than that of 100 km. At 3 days, it was significantly higher than pre-race and 100 km, recovering at 5 days. In terms of FSH, it decreased at 100 km, 1 day, and 3 days more than pre-race but recovered at 5 days. TSH was higher at 1 day and 5 days compared to pre-race. T3 was only higher at 100 km than pre-race. T4 was higher till 5 days at 100 km than pre-race. Free T4 increased more significantly at 100 km than pre-race. Conclusion: In terms of severe long distance running, LH and FSH which belong to hormone from anterior lobe as well as T3, T4, and Free T4 which belong to thyroid hormone showed their variation within the standard range. However, TSH showed abnormal increase from enhanced concentration of blood after marathon becoming hyper-activation even during the recovery period.

Differential Expression of Glycoprotein Hormones in Equine Placenta and Pituitary (말 태반과 뇌하수체에서 당단백질 호르몬의 특이적인 발현)

  • Min, Kwan-Sik
    • Development and Reproduction
    • /
    • v.4 no.1
    • /
    • pp.87-93
    • /
    • 2000
  • Equine chorionic gonadotropin (eCG) consists of highly glycosylated noncovalently linked $\alpha$- and $\beta$-subunits and belongs to the glycoprotein hormone family that includes lutropin (LH), follitropin (FSH), and thyrotropin (FSH). eCG is a unique member of the gonadotropin family because it elicits response characteristics of both FSH and LH in other species than the hone. eCG is synthesized and secreted by trophoblastic cells of the endometial cups between 40 and 130 days of gestation. In the present study, mRNA expression ratio of eCG, eLH and eFSH $\alpha$- and $\beta$-subunints was investigated in the placenta and pituitary. mRNA was extracted from equine placenta on day 70 of gestation and from pituitary of male horse (27 month-old). When the expression of both subunit mRNAs of eCG in the equine placenta was compared by Northern blotting, the expression of the $\beta$ -subunit mRNA was relatively greater than that of the $\alpha$-subunit. And mRNA expression of $\alpha$-, LH $\beta$- and FSH $\beta$-subunits was analysed in the equine pituitary. An $\alpha$-subunit was revealed with a size of approximately 0.8 kb. FSH $\beta$-subunit mRNA also was detected out 1.8 kb. It is the same size of the FSH $\beta$ -subunit mRNA cloned. The intensity of $\alpha$-subunit mRNA was greater than that of the $\beta$-subunit suggesting that the expression of $\alpha$ -subunit was dominant in the equine anterior pituitary. Thus, the subunit mRNA levels seem to be independently regulated and their imbalance may account for differences in the quantities of $\alpha$- and $\beta$-subunits in the equine placenta and pituitary.

  • PDF

Presence of Pituitary Specific Transcription Factor Pit-1 in the Rat Brain: Intracerebroventricular Administration of Antisense Pit-1 Oligodeoxynucleotide Decreases Brain Prolactin mRNA Level

  • Tae Woo Kim;Hyun-Ju Kim;Byung Ju Lee
    • Animal cells and systems
    • /
    • v.3 no.3
    • /
    • pp.311-317
    • /
    • 1999
  • Prolactin (PRL) was reported to be locally synthesized in many brain areas including the hypothalamus, thalamus (TH) and hippocampus (HIP). In the pituitary lactotrophs, PRL synthesis is dependent upon a pituitary-specific transcription factor, Pit-1. In the present study, we attempted to identify Pit-1 or Pit-1-like protein in brain areas known as the synthetic sites of PRL. Reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot analysis showed the same Pit-1 transcripts in brain areas such as the medial basal hypothalamus (MBH), preoptic area (POA), TH, and HIP with the Pit-1 transcripts in the anterior pituitary (AP). Electrophoretic mobility shift assay (EMSA) was run with nuclear protein extracts from brain tissues using a double strand oligomer probe containing a putative Pit-1 binding domain. Shifted bands were found in EMSA results with nuclear proteins from MBH, POA, TH and HIP. Specific binding of the Pit-1-like protein was further confirmed by competition with an unlabeled cold probe. Antisense Pit-1 oligodeoxynucleotide (Pit-1 ODN), which was designed to bind to the Pit-1 translation initiation site and block Pit-1 biosynthesis, was used to test Pit-1 dependent brain PRL transcription. Two nmol of Pit-1 ODN was introduced into the lateral ventricle of a 60-day old male rat brain. RNA blot hybridization and in situ hybridization indicated a decrease of PRL mRNA signals by the treatment of Pit-1 ODN. Taken together, the present study suggests that Pit-1 may play an important role in the transcriptional regulation of local PRL synthesis in the brain.

  • PDF

Dual Effects of Norepinephrine on $GABA_A$-Mediated Spontaneous Postsynaptic Currents in the Rat Hypothalamic Paraventricular Neurons.

  • Han, Seong-Kyu;Ryu, Pan-Dong
    • Proceedings of the Korean Biophysical Society Conference
    • /
    • 1999.06a
    • /
    • pp.58-58
    • /
    • 1999
  • The paraventricular nucleus (PVN) is a complex structure comprised of several different populations of cells divided into two main groups, the magnocellular (type I) neurons which secrete vasopressin and oxytocin and the parvocellular (type II) neurons which regulate hormone secretion from the anterior pituitary.(omitted)

  • PDF