Endocrine influences on growth and pigmentation of embryonic down feather cells

Development ◽  
1968 ◽  
Vol 20 (3) ◽  
pp. 319-327
Author(s):  
Leland G. Johnson
Keyword(s):  
Chick Embryo ◽  
Pituitary Gland ◽  
Developmental Studies ◽  
Pigment Granules ◽  
And Control ◽  
Feather Development

Rawles (1960) and Hamilton (1952) have outlined the development of the down feather. Details of the development and interaction of the epidermal constituents and melanocytes of the down feather were reported by Watterson (1942) and Goff (1949) described the development of the mesodermal portions of the feather. There have been several reports that normal down feather development is dependent upon undisturbed endocrine balance. One of the techniques for alteration of normal endocrine patterns in the chick embryo is the complete extirpation of the rudiments of the pituitary gland (Fugo, 1940) and many developmental studies have been based upon this method of ‘hypophysectomy’ by partial decapitation (see Hinni & Watterson, 1963). Several of these studies have cited gross effects of this operation on down feather development. Fugo (1940) found pronounced differences between operated and control embryos in length and general pigmentation of down feathers along with a ‘tremendous increase’ in the number of pigment granules in individual barbule cells of decapitated embryos.

Effect of hypophysectomy by partial decapitation and treatment with thiourea on iodine metabolism in the developing chick embryo

1983 ◽  
Vol 98 (1) ◽  
pp. 113-119 ◽  
Author(s):  
Nicole Daugèras-Bernard ◽  
François Lachiver
Keyword(s):  
Thyroid Gland ◽  
Chick Embryo ◽  
Pituitary Gland ◽  
Direct Action ◽  
Thyroid Stimulating Hormone ◽  
Yolk Sac ◽  
Pituitary Hormone ◽  
Iodine Metabolism ◽  
Tsh Secretion ◽  
And Control

The hypothesis of an action of the pituitary gland of the developing chick embryo in the transfer of iodide from the yolk of the egg to the circulation of the embryo, through the yolk sac, was tested. Plasma iodide levels and thyroidal iodine contents were determined in hypophysectomized (by partial decapitation), thiourea-injected and control embryos. From day 11 of incubation these parameters were always lower in the 'hypophysectomized' embryos than in controls, and plasma iodide levels of the thiourea-treated embryos were higher than those of controls. These results indicate a reduced iodide transfer from the yolk to the 'hypophysectomized' embryo, and an increased iodide transfer to the thioureatreated embryo. This occurred in spite of a reduced thyroid hormonal secretion in both series. The pituitary gland could therefore have a direct action (not through the thyroid gland) at the yolk sac level, to augment the transfer of iodide from the yolk in intact embryos from day 11 to the end of incubation. Thyroid-stimulating hormone (TSH) could be the pituitary hormone acting at the yolk sac level, the increased iodide transfer observed in the thiourea-injected embryos being due to a raised TSH secretion responding to the decreased plasma thyroxine levels.

A STUDY OF THE INHIBITORY EFFECTS OF CHICK WHOLE EYE EXTRACT ON THE DEVELOPMENT OF THE LENS OF THE CHICK EMBRYO IN VITRO

1966 ◽  
Vol 44 (4) ◽  
pp. 661-676 ◽  
Author(s):  
Robert P. Thompson
Keyword(s):  
Chick Embryo ◽  
Nutrient Medium ◽  
Inhibitory Effect ◽  
Reactive System ◽  
Vesicle Formation ◽  
Inhibitory Effects ◽  
Muscle Extract ◽  
Lens Vesicle ◽  
And Control

To demonstrate the phenomenon of homologous inhibition by clearly interpretable results in a readily reactive system, experiments were carried out to study the effect of chick whole eye extract on the development of the vesicular lens of the chick embryo in vitro. The heads of embryos of 11 through 13 somites were explanted onto nutrient medium diluted with varying amounts of the extract, and cultured for 30 hours. A total of 35 embryos exposed to concentrations of 1:1, 1:2, and 1:4 (extract to medium) showed complete inhibition of lens vesicle formation. Of a total of 53 embryos on concentrations of 1:8, 1:16, 1:32, and 1:64, more than 50% showed inhibition of vesicle formation. The inhibitory effect disappeared at a concentration of 1:128. Control material exposed to some equivalent concentrations of nutrient medium – saline mixtures showed inhibition of vesicle formation in only 15% of 33 embryos. Of a total of 27 control embryos exposed to ventricular muscle extract, approximately one-third showed inhibition of vesicle formation at concentrations of 1:8 and 1:16, with the inhibitory effect disappearing at 1:32. The implications of this result are discussed. Other factors and control experiments are described and their value is assessed.

scholarly journals Reporter Expression, Induced by a Growth Hormone Promoter-Driven Cre Recombinase (rGHp-Cre) Transgene, Questions the Developmental Relationship between Somatotropes and Lactotropes in the Adult Mouse Pituitary Gland

Endocrinology ◽  
2007 ◽  
Vol 148 (5) ◽  
pp. 1946-1953 ◽  
Author(s):  
Raul M. Luque ◽  
Geraldine Amargo ◽  
Shinya Ishii ◽  
Corrinne Lobe ◽  
Roberta Franks ◽  
...  
Keyword(s):  
Pituitary Gland ◽  
Transgenic Mouse ◽  
Anterior Pituitary ◽  
Adult Mouse ◽  
Small Subset ◽  
Parental Line ◽  
Pituitary Cells ◽  
Placental Alkaline Phosphatase ◽  
Developmental Studies ◽  
Mouse Pituitary

This report describes the development and validation of the rGHp-Cre transgenic mouse that allows for selective Cre-mediated recombination of loxP-modified alleles in the GH-producing cells of the anterior pituitary. Initial screening of the rGHp-Cre parental line showed Cre mRNA was specifically expressed in the anterior pituitary gland of adult Cre+/− mice and cephalic extracts of e17 Cre+/− fetuses. Heterozygote rGHp-Cre transgenic mice were crossbred with Z/AP reporter mice to generate Cre+/−,Z/AP+/− offspring. In this model system, the GH promoter-driven, Cre-mediated recombination of the Z/AP reporter leads to human placental alkaline phosphatase (hPLAP) expression that serves to mark cells that currently produce GH, in addition to cells that would have differentiated from GH cells but currently do not express the GH gene. Double immunocytochemistry of adult male and female Cre+/−,Z/AP+/− pituitary cells revealed the majority (∼99%) of GH-producing cells of the anterior pituitary also expressed hPLAP, whereas ACTH-, TSH-, and LH-producing cells were negative for hPLAP, confirming previous reports that corticotropes, thyrotropes, and gonadotropes develop independently of the somatotrope lineage. A small subset (∼10%) of the prolactin-producing cells was positive for hPLAP, consistent with previous reports showing lactotropes can arise from somatotropes during pituitary development. However, the fact that 90% of prolactin-producing cells were negative for hPLAP suggests that the majority of lactotropes in the adult mouse pituitary gland develop independently of the somatotrope lineage. In addition to developmental studies, the rGHp-Cre transgenic mouse will provide a versatile tool to study the role of a variety of genes in somatotrope function and neoplastic transformation.

scholarly journals Effect of Different Doses of Doxorubicin on Pituitary Gland and Some Testicular Function in Adult Male Rabbits

2013 ◽  
Vol 37 (1) ◽  
pp. 121-128
Author(s):  
Baraa N. AL-Okaily
Keyword(s):  
Pituitary Gland ◽  
Adult Male ◽  
Detrimental Effect ◽  
Control Group ◽  
Histopathological Changes ◽  
Control Groups ◽  
The Third ◽  
Histopathological Studies ◽  
And Control ◽  
Different Doses

The present study was designed to search out the effect of different doses of doxorubicin some functions of pituitary gland and testes in adult male rabbits. Twenty adult male rabbits were randomly divided into four equal groups and treated for 28 days as follows: first group (control) were injected with normal saline; second group (GI) were injected with doxorubicin 3 mg/ kg B.W., while animals in the third group (GII) and fourth group (GIII) injected with 3.5 and 4 mg/ kg body weight of doxorubicin respectively, all animals were injected twice a week via ear vein. At the end of experiment fasting blood (8-10 hrs) samples were collected. Blood was drawn by cardiac puncture technique and serum was collected for measuring the hormones, Follicular Stimulating Hormone (FSH), Luteinizing Hormone (LH), and Testosterone (T). In addition, sections from pituitary gland and testes were taken for histopathological studies. The results showed significant increase (P<0.05) in serum FSH, LH and T levels in group (GIII) as compared to GI, GI and control groups. Beside significant increases in T levels was observed in GII as compared to control group. Sever histopathological changes was observed in testes including thickness of basement membrane, protienous material in lumen of somniferous tubules and pituitary gland showed fibrosis, faculation of epithelial cell in all treated groups. In conclusion different doses of doxorubicin have detrimental effect on pituitary gland and male reproductive system of rabbits

scholarly journals EFFECT OF SODIUM MONOFLUOROACETATE ON THE MULTIPLICATION OF INFLUENZA VIRUSES, MUMPS VIRUS, AND PNEUMONIA VIRUS OF MICE (PVM)

1952 ◽  
Vol 96 (6) ◽  
pp. 531-548 ◽  
Author(s):  
William J. Mogabgab ◽  
Frank L. Horsfall
Keyword(s):  
Chick Embryo ◽  
Influenza A ◽  
Virus Titer ◽  
Mumps Virus ◽  
Influenza Viruses ◽  
Mouse Lung ◽  
Influenza B Virus ◽  
Influenza B ◽  
Chick Embryos ◽  
And Control

Sodium fluoroacetate, given after virus inoculation in doses of 3 to 4 mg. per kg. in mice or 2 mg. in chick embryos, caused only a slight delay in the multiplication of the PR8 strain of influenza A virus in the mouse lung and of PR8 or the Lee strain of influenza B virus in the allantoic sac. The quantities of the compound used were sufficient to cause approximately 10 to 20 per cent mortality in mice and 100 per cent in chick embryos. The use of small virus inocula did not markedly increase the effect of sodium fluoroacetate on the multiplication of PR8 or Lee in the chick embryo and maximal titers were obtained in all cases. In contrast to the findings in the chick embryo, sodium fluoroacetate caused a definite delay in the multiplication of Lee virus in the mouse lung but did not affect the final virus titer. Sodium fluoroacetate in like amounts caused only a minimal delay in the multiplication of pneumonia virus of mice (PVM) in the mouse lung or of mumps virus in the chick embryo. With both PVM and mumps virus, maximal titers were obtained almost simultaneously in fluoroacetate and control animals. When three daily injections of the compound were given to mice infected previously with PVM, a definite diminution in the virus titer was demonstrable. However, pretreatment with three daily injections of the compound caused no alteration in the capacity of mice to support the multiplication of PVM. From the results of these experiments, it appears that the cellular metabolic processes blocked by sodium fluoroacetate are not essential for the multiplication of influenza viruses, mumps virus, or pneumonia virus of mice (PVM).

Effects of chromium picolinate on the viability of chick embryo fibroblast

2013 ◽  
Vol 33 (4) ◽  
pp. 403-413 ◽  
Author(s):  
Y Bai ◽  
X Zhao ◽  
C Qi ◽  
L Wang ◽  
Z Cheng ◽  
...  
Keyword(s):  
Chick Embryo ◽  
Morphological Changes ◽  
Nutritional Supplement ◽  
Ion Concentration ◽  
Chromium Picolinate ◽  
Control Group ◽  
Chick Embryo Fibroblast ◽  
Intracellular Calcium Ion ◽  
Calcium Ion Concentration ◽  
And Control

Chromium picolinate (CrPic), which is used as a nutritional supplement and to treat type 2 diabetes, has gained much attention because of its cytotoxicity. This study evaluated the effects of CrPic on the viability of the chick embryo fibroblast (CEF) using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, morphological detection, and flow cytometry. The results show that lower concentrations of CrPic (8 and 16 μM) did not damage CEF viability ( p > 0.05). However, higher CrPic concentrations (400 and 600 μM) indicated a highly significant effect on the production of intracellular reactive oxygen species, alteration of mitochondrial membrane potential, intracellular calcium ion concentration, and the apoptosis rate ( p < 0.01), contrary to lower CrPic concentrations (8 and 16 μM) and control group. Moreover, apoptotic morphological changes induced by these processes in CEF were confirmed using Hoechst 33258 staining. Cell death induced by higher concentrations of CrPic was caused by an apoptotic and a necrotic mechanism, whereas the main mechanism of oxidative stress-induced mitochondrial dysfunction was apoptotic death.

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