The pituitary gland of the coelacanth fish Latimeria chalumnae Smith: General structure and adenohypophysial cell types

1975 ◽  
Vol 163 (3) ◽  
pp. 291-311 ◽  
Author(s):  
J. A. M. van Kemenade ◽  
J. W. Kremers
Keyword(s):  
Pituitary Gland ◽  
General Structure ◽  
Cell Types ◽  
Latimeria Chalumnae

The Pituitary Gland of the Sockeye (Oncorhynchus nerka) During Sexual Maturation and Spawning

1967 ◽  
Vol 24 (8) ◽  
pp. 1791-1810 ◽  
Author(s):  
A. P. van Overbeeke ◽  
J. R. McBride
Keyword(s):  
Pituitary Gland ◽  
Sexual Maturation ◽  
Sockeye Salmon ◽  
Oncorhynchus Nerka ◽  
Gonad Development ◽  
Cell Types ◽  
Limited Extent ◽  
Degenerative Alterations ◽  
Different Cell Types

This communication presents the results of a study of the pituitaries of 150 sockeye salmon in various stages of sexual maturation from the time they entered freshwater till after completion of spawning. In the homologue of the adenohypophysis, nine different cell types were distinguished. On the basis of changes in tinctorial and histochemical properties and relative proportions of each of these cells, it was concluded that the sockeye pituitary contains six different hormone-producing cell types. One of these probably possesses a gonadotrophic function. Degenerative phenomena in the pituitary were found in the sexually ripe and the spent salmon, but only to a limited extent. The implications of the changes in the occurrence of the six different cell types and the degenerative alterations are discussed in relation to gonad development and the death after spawning.

scholarly journals Immunocytochemical demonstration of tissue-type plasminogen activator in endocrine cells of the rat pituitary gland.

1985 ◽  
Vol 101 (1) ◽  
pp. 305-311 ◽  
Author(s):  
P Kristensen ◽  
L S Nielsen ◽  
J Grøndahl-Hansen ◽  
P B Andresen ◽  
L I Larsson ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Pituitary Gland ◽  
Endocrine Cells ◽  
Large Population ◽  
Cell Types ◽  
Anterior Lobe ◽  
Tissue Type ◽  
Intermediate Lobe ◽  
Posterior Lobe ◽  
Rat Pituitary

We immunocytochemically stained rat pituitary glands using antibodies against plasminogen activators of the tissue type (t-PA) and the urokinase type (u-PA). A large population of endocrine cells in the anterior lobe of the gland displayed intense cytoplasmic immunoreactivity with anti-t-PA. In some areas of the intermediate lobe we found a weak staining, and we observed weakly staining granular structures in the posterior lobe. Controls included absorption of the antibodies with highly purified t-PA. In addition, SDS PAGE followed by immunoblotting of pituitary gland extracts revealed only one band with an electrophoretic mobility similar to that of t-PA when stained with anti-t-PA IgG. No u-PA immunoreactivity was detected in the rat pituitary gland. Sequential staining experiments using antibodies against growth hormone and t-PA demonstrated that the t-PA-immunoreactive cells constitute a large subpopulation of the growth hormone-containing cells. These findings represent the first direct evidence for the presence of t-PA in cell types other than endothelial cells in the intact normal organism. In this article we discuss the implications of the results for a possible role of t-PA in the posttranslational processing of prohormones.

scholarly journals Epithelial cell integrin β1 is required for developmental angiogenesis in the pituitary gland

2016 ◽  
Vol 113 (47) ◽  
pp. 13408-13413 ◽  
Author(s):  
Kathleen M. Scully ◽  
Dorota Skowronska-Krawczyk ◽  
Michal Krawczyk ◽  
Daria Merkurjev ◽  
Havilah Taylor ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Pituitary Gland ◽  
Molecular Mechanisms ◽  
Cell Types ◽  
Endocrine Function ◽  
Vascular Density ◽  
Integrin Β1 ◽  
Coordinated Development ◽  
Mouse Pituitary ◽  
Insight Into

As a key component of the vertebrate neuroendocrine system, the pituitary gland relies on the progressive and coordinated development of distinct hormone-producing cell types and an invading vascular network. The molecular mechanisms that drive formation of the pituitary vasculature, which is necessary for regulated synthesis and secretion of hormones that maintain homeostasis, metabolism, and endocrine function, remain poorly understood. Here, we report that expression of integrin β1 in embryonic pituitary epithelial cells is required for angiogenesis in the developing mouse pituitary gland. Deletion of pituitary epithelial integrin β1 before the onset of angiogenesis resulted in failure of invading endothelial cells to recruit pericytes efficiently, whereas deletion later in embryogenesis led to decreased vascular density and lumen formation. In both cases, lack of epithelial integrin β1 was associated with a complete absence of vasculature in the pituitary gland at birth. Within pituitary epithelial cells, integrin β1 directs a large transcriptional program that includes components of the extracellular matrix and associated signaling factors that are linked to the observed non–cell-autonomous effects on angiogenesis. We conclude that epithelial integrin β1 functions as a critical and canonical regulator of developmental angiogenesis in the pituitary gland, thus providing insight into the long-standing systems biology conundrum of how vascular invasion is coordinated with tissue development.

Expression, distribution, regulation and function of IGFs in the ovine fetal pituitary

1995 ◽  
Vol 14 (3) ◽  
pp. 323-336 ◽  
Author(s):  
F Lü ◽  
K Yang ◽  
V K M Han ◽  
J R G Challis
Keyword(s):  
Pituitary Gland ◽  
Endocrine Cells ◽  
Cell Types ◽  
Pars Intermedia ◽  
Pars Distalis ◽  
Paracrine Factors ◽  
Pomc Mrna ◽  
Pars Nervosa ◽  
Igf I ◽  
And Function

ABSTRACT Activation of the fetal pituitary-adrenal axis is crucial for fetal organ maturation and the onset of parturition in sheep. Many factors including corticotrophin-releasing hormone (CRH) and arginine vasopressin secreted from the hypothalamus, and growth factors produced within the pituitary may be involved in the regulation of maturation of the fetal pituitary gland. IGFs have mitogenic and differentiation-promoting capacities in a variety of organs and are synthesized as paracrine factors within developing tissues. However, there is little information concerning the synthesis, distribution, regulation and function of IGFs in the fetal pituitary gland at different times during pregnancy. Therefore, we have localized IGF-I and IGF-II mRNAs and peptides, and determined the effect of cortisol on the level of IGF-II mRNAs in the pituitary glands of developing sheep fetuses. We examined the possible effects of IGFs on corticotroph function in cultures of adenohypophysial cells from term fetuses. Seven species of IGF-II transcripts of 1·2–6·0 kb were identified by Northern blot analysis in the pituitary gland of fetuses between day 60 of gestation and term (day 145). The levels of IGF-II mRNAs did not change significantly during pregnancy, although there was a trend for the presence of higher levels of IGF-II mRNAs at day 60 of gestation. IGF-I mRNA was not detectable. By in situ hybridization, IGF-II mRNA was localized to non-endocrine cells and to cells lining the blood vessels of the pars distalis, to some presumed endocrine cells in the pars distalis and pars intermedia, and to clusters of cells in the pars nervosa. In contrast, IGF-I and IGF-II peptides were detected in the presumed endocrine cells in the pars distalis and pars intermedia but not in the pars nervosa. Incubation of adenohypophysial cells from term fetuses with IGF-I, but not IGF-II, for 48 h increased specific 125I-Tyr-ovine CRH binding. However, neither IGF-I nor IGF-II had any significant effects on the basal or CRH-stimulated immunoreactive (ir)-ACTH output, the level of POMC mRNA or the number of ir-ACTH positive cells. Infusion of cortisol to fetuses starting at day 96 of gestation for 100 h or at days 120–125 of gestation for 84 h did not affect the level of IGF-II mRNAs in the pars distalis but decreased the levels of POMC mRNA. These results are consistent with IGFs having the potential to influence fetal pituitary function, although probably on cell types other than the corticotrophs. The likely sources of IGFs may be predominantly local (IGF-II) or from extrapituitary sources (IGF-I).

scholarly journals LOCALIZATION OF PHOSPHATASE ACTIVITIES IN THE RAT ANTERIOR PITUITARY GLAND

1972 ◽  
Vol 20 (1) ◽  
pp. 1-12 ◽  
Author(s):  
GEORGES PELLETIER ◽  
ALEX B. NOVIKOFF
Keyword(s):  
Golgi Apparatus ◽  
Pituitary Gland ◽  
Anterior Pituitary ◽  
Secretory Cell ◽  
Cell Types ◽  
Anterior Pituitary Gland ◽  
Pituitary Cells ◽  
Blood Capillaries ◽  
Phosphatase Activities ◽  
Thiamine Pyrophosphatase

All five known secretory cell types of the rat anterior pituitary gland display nucleoside diphosphatase (NDPase) activity throughout the endoplasmic reticulum (ER), including the nuclear envelope but not the specialized region of ER at the inner aspect of the Golgi apparatus known as GERL. The functions of the ER diphosphatase are currently unknown. However, speculations concerning its association with glucuronyl transferase may focus on the metabolic roles of the ER in pituitary cells other than those directly related to secretory protein transport. The gonadotrophs have been studied for thiamine pyrophosphatase and acid phosphatase activities as well as NDPase activity. The results suggest that the secretory granules of gonadotrophs arise from GERL and not from the inner element of the Golgi apparatus. The innermost Golgi element of this cell type shows NDPase and thiamine pyrophosphatase activities and appears to be composed, in part at least, of anastomosing tubules. Nucleoside phosphatase activity is also present at the surfaces of all five secretory cell types and between the cells and adjacent blood capillaries.

scholarly journals A Novel Nonsense Mutation in the Pit-1 Gene: Evidence for a Gene Dosage Effect

2003 ◽  
Vol 88 (3) ◽  
pp. 1241-1247 ◽  
Author(s):  
Yukiko Hashimoto ◽  
Mariangela Cisternino ◽  
Laurie E. Cohen
Keyword(s):  
Pituitary Gland ◽  
Nonsense Mutation ◽  
Gene Dosage ◽  
Present Report ◽  
Growth Failure ◽  
Cell Types ◽  
Specific Gene ◽  
Specific Domain ◽  
Gene Dosage Effect ◽  
Α Helix

The POU transcription factor Pit-1 functions in the development of somatotrophs, lactotrophs, and thyrotrophs of the anterior pituitary gland. It also plays a role in cell-specific gene expression and regulation of the gene products from these cell types, GH, prolactin, and TSH, respectively. In the present report we studied a patient with severe growth failure. Provocative studies revealed undetectable GH, prolactin, and TSH levels, and her pituitary gland was hypoplastic on magnetic resonance imaging. She had a novel homozygous nonsense mutation in the 3′ end of the first α-helix of the POU-specific domain of the Pit-1 gene. This mutation results in a truncated protein with loss of most of the Pit-1 DNA-binding domains. Interestingly, her parents, who each have one mutant allele, have evidence of mild endocrine dysfunction. Thus, two normal copies of the Pit-1 gene appear necessary for full Pit-1 gene function.

scholarly journals Imaging of Endoplasmic Reticulum Ca2+ in the Intact Pituitary Gland of Transgenic Mice Expressing a Low Affinity Ca2+ Indicator

2021 ◽  
Vol 11 ◽  
Author(s):  
Jonathan Rojo-Ruiz ◽  
Paloma Navas-Navarro ◽  
Lucía Nuñez ◽  
Javier García-Sancho ◽  
María Teresa Alonso
Keyword(s):  
Endoplasmic Reticulum ◽  
Pituitary Gland ◽  
Transgenic Mouse ◽  
Calcium Release ◽  
Cell Types ◽  
Thyrotropin Releasing Hormone ◽  
Pituitary Cells ◽  
Releasing Hormone ◽  
Pituitary Glands ◽  
Calcium Induced Calcium Release

The adenohypophysis contains five secretory cell types (somatotrophs, lactotrophs, thyrotrophs, corticotrophs, and gonadotrophs), each secreting a different hormone, and controlled by different hypothalamic releasing hormones (HRHs). Exocytic secretion is regulated by cytosolic Ca2+ signals ([Ca2+]C), which can be generated either by Ca2+ entry through the plasma membrane and/or by Ca2+ release from the endoplasmic reticulum (ER). In addition, Ca2+ entry signals can eventually be amplified by ER release via calcium-induced calcium release (CICR). We have investigated the contribution of ER Ca2+ release to the action of physiological agonists in pituitary gland. Changes of [Ca2+] in the ER ([Ca2+]ER) were measured with the genetically encoded low-affinity Ca2+ sensor GAP3 targeted to the ER. We used a transgenic mouse strain that expressed erGAP3 driven by a ubiquitous promoter. Virtually all the pituitary cells were positive for the sensor. In order to mimick the physiological environment, intact pituitary glands or acute slices from the transgenic mouse were used to image [Ca2+]ER. [Ca2+]C was measured simultaneously with Rhod-2. Luteinizing hormone-releasing hormone (LHRH) or thyrotropin releasing hormone (TRH), two agonists known to elicit intracellular Ca2+ mobilization, provoked robust decreases of [Ca2+]ER and concomitant rises of [Ca2+]C. A smaller fraction of cells responded to thyrotropin releasing hormone (TRH). By contrast, depolarization with high K+ triggered a rise of [Ca2+]C without a decrease of [Ca2+]ER, indicating that the calcium-induced calcium-release (CICR) via ryanodine receptor amplification mechanism is not present in these cells. Our results show the potential of transgenic ER Ca2+ indicators as novel tools to explore intraorganellar Ca2+ dynamics in pituitary gland in situ.

scholarly journals Ontogeny of Adenohypophyseal Cells, Pituitary Gland Development and Structure in Adults of Astyanax Lacustris (Teleostei, Characidae): an Emerging Neotropical Fish Species

2021 ◽  
Author(s):  
Giovana Souza Branco ◽  
Lázaro Wender O. De Jesus ◽  
Monica Cassel ◽  
Chayrra Chehade ◽  
Marília de Paiva Camargo ◽  
...  
Keyword(s):  
Pituitary Gland ◽  
Early Development ◽  
Fish Species ◽  
Cell Types ◽  
South American ◽  
Neotropical Fish ◽  
Future Studies ◽  
Commercial Importance ◽  
Gland Morphogenesis ◽  
Gland Development

Abstract Pituitary gland morphogenesis of the adenohypophyseal (AH) cells of Astyanax lacustris are presented herein. This Characiformes species show great ecological and commercial importance, and it has been increasingly used as a biological model. The first AH cells of A. lacustris were detected at 1 dah by the immunostaining of PRL producing cells. The morphology of the gland presented changes in shape throughout the development, starting elongated but more oval at the end. The neurohypophysis was differentiated at 3 dah, along with the identification of ACTH, MSH, TSH, and FSH producing cells. Identification of the immunoreactive cells to anti-LH, anti-SL, and anti-GH antibodies occurred at 5 dah. At 20 dah, an increase in pituitary size and the presence of the pituitary stalk were observed. At 60 dah, the pituitary already had the same shape seen in adults. The ontogeny of adenohypophyseal cells in A. lacustris corroborates the heterogeneity in the appearance of these cell types in teleosts and suggests that these hormones actively participate during the early development of this species. Our results collaborate with the understanding of the morphogenesis of the hypothalamic-pituitary-gonadal axis in South American teleosts, showing essential data for the development of future studies related to pituitary morphophysiology.

FUNCTIONAL SIGNIFICANCE OF THE CELLS IN THE PARS ANTERIOR OF THE PITUITARY GLAND OF THE MUSK SHREW (SUNCUS MURINUS L.)

1978 ◽  
Vol 79 (1) ◽  
pp. 91-NP ◽  
Author(s):  
D. R. NAIK ◽  
C. J. DOMINIC
Keyword(s):  
Pituitary Gland ◽  
Mammalian Species ◽  
Cell Types ◽  
Suncus Murinus ◽  
Unilateral Adrenalectomy ◽  
Musk Shrew ◽  
Gonadotrophin Secretion ◽  
Pars Anterior ◽  
Experimental Treatments

Seven morphologically and tinctorially distinct types of cell (types 1–) have been distinguished in the pars anterior of the pituitary gland of the musk shrew (Suncus murinus L.). On the basis of their responses to various experimental stimuli, these cell types were correlated with the secretion of various trophic hormones. Type 1 cells exhibited conspicuous changes after thyroidectomy or inactivation of the thyroid gland and hence appeared to be the source of TSH. Types 2 and 3 cells responded to gonadectomy and administration of androgens, which suggests that they were associated with gonadotrophin secretion. The granules of the type 2, but not the type 3 cells could be extracted with 10% trichloroacetic acid, which may indicate that type 2 and 3 cells secrete FSH and LH respectively. After the administration of either reserpine or oestrogen, the type 4 cells underwent hypertrophy and hyperplasia, which suggests that they were the likely source of prolactin. Type 6 cells, which are distinguishable from type 4 cells by their thinly dispersed erythrosinophilic granulation, showed conspicuous changes after unilateral adrenalectomy, administration of metyrapone or exposure to stress and may therefore be responsible for secretion of ACTH. Type 5 cells tinctorially resembled the somatotrophic cells of other mammalian species and did not respond to any of the experimental treatments used in the present study. It is therefore possible that these cells have a somatotrophic function. The possible significance of type 7 cells has been discussed previously.

Sign in / Sign up

Export Citation Format

Share Document