Effects of Thiourea Treatment on Sexually Maturing and Gonadectomized Male Sockeye Salmon (Oncorhynchus nerka)

1975 ◽  
Vol 32 (1) ◽  
pp. 11-19 ◽  
Author(s):  
J. R. McBride ◽  
A. P. van Overbeeke
Keyword(s):  
Pituitary Gland ◽  
Sockeye Salmon ◽  
Cell Types ◽  
Pars Distalis ◽  
Secondary Sexual Characteristics ◽  
Sexual Characteristics ◽  
Visible Effect ◽  
Induced Changes ◽  
Thyroid Epithelium ◽  
Thiourea Treatment

Adult male sockeye salmon in the final stage of sexual maturation were treated with thiourea for periods of 7–14 wk. The treatment produced strong histological thyroid stimulation but no visible effect on spermatogenesis or development of secondary sexual characteristics. The drug did not affect the interrenal hypertrophy that commonly occurs in these salmon, but slightly inhibited the increase in thickness of the skin. Thiourea induced changes in the pars distalis of the pituitary gland, involving several cell-types, including retardation of gonadotrop development.In gonadectomized fish, thiourea affected neither the skin, nor the interrenal tissue. It caused a marked increase in the height of the thyroid epithelium, correlated with hypertrophy, degranulation, and some vacuolization of PAS-positive cells in the dorso-caudal area of the proximal pars distalis of the pituitary gland. Therefore, these last cells are considered thyrotrops.

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.

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 Cardiac Performance of Free-Swimming Wild Sockeye Salmon during the Reproductive Period

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
T S Prystay ◽  
R de Bruijn ◽  
K S Peiman ◽  
S G Hinch ◽  
D A Patterson ◽  
...  
Keyword(s):  
Heart Rate ◽  
Sockeye Salmon ◽  
Reproductive Period ◽  
Cardiac Performance ◽  
Survival Duration ◽  
Reproductive Behaviors ◽  
Spawning Period ◽  
Secondary Sexual Characteristics ◽  
Sexual Characteristics ◽  
Secondary Sexual

Synopsis Researchers have surmised that the ability to obtain dominance during reproduction is related to an individual’s ability to better sequester the energy required for reproductive behaviors and develop secondary sexual characteristics, presumably through enhanced physiological performance. However, studies testing this idea are limited. Using sockeye salmon (Oncorhynchus nerka), we explored the relationship between heart rate and dominance behavior during spawning. We predicted that an individual’s reproductive status and energy requirements associated with dominance can be assessed by relating routine heart rate to changes in spawning status over time (i.e., shifts among aggregation, subordinance, and dominance). Thus, we used routine heart rate as a proxy of relative energy expenditure. Heart rate increased with temperature, as expected, and was higher during the day than at night, a known diel pattern that became less pronounced as the spawning period progressed. Routine heart rate did not differ between sexes and average heart rate of the population did not differ among reproductive behaviors. At the individual level, heart rate did not change as behavior shifted from one state to another (e.g., dominance versus aggregation). No other trends existed between routine heart rate and sex, secondary sexual characteristics, survival duration or spawning success (for females only). Therefore, while our study revealed the complexity of the relationships between cardiac performance and reproductive behaviors in wild fish and demonstrated the importance of considering environmental factors when exploring individual heart rate, we found no support for heart rate being related to specific spawning behavioral status or secondary sexual characteristics.

Histological Effects of 11-Ketotestosterone, 17α-Methyltestosterone, Estradiol, Estradiol Cypionate, and Cortisol on the Interrenal Tissue, Thyroid Gland, and Pituitary Gland of Gonadectomized Sockeye Salmon (Oncorhynchus nerka)

1971 ◽  
Vol 28 (4) ◽  
pp. 477-484 ◽  
Author(s):  
A. P. van Overbeeke ◽  
J. R. McBride
Keyword(s):  
Thyroid Gland ◽  
Sex Steroids ◽  
Sockeye Salmon ◽  
Marked Effect ◽  
Anterior Part ◽  
Oncorhynchus Nerka ◽  
Control Fish ◽  
Slight Reduction ◽  
Pars Distalis ◽  
Visible Effect

Effects of two androgens, two estrogens, and cortisol in gonadectomized sockeye salmon (Oncorhynchus nerka) were investigated. Males were injected with 11-ketotestosterone, 17α-methyltestosterone, or cortisol for 4 or 7 weeks. Females were injected with estradiol, estradiol cypionate, or cortisol for 8 weeks.Both the androgens and the estrogens caused interrenal hypertrophy. The effect of 17α-methyltestosterone was stronger than that of 11-ketotestosterone, and of the two estrogens used, estradiol cypionate exerted the most marked effect. Cortisol brought about a slight atrophy of the interrenal tissue.A pronounced histological activation of the small thyroid follicles was induced by the two androgens. The estrogens exerted no visible effect on the thyroid gland, and cortisol treatment caused a slight reduction in the height of the follicular epithelium.In the gonadectomized control fish of both sexes, gonadotrophs were small and practically all devoid of granules. All four sex steroids induced the appearance of many granulated PAS-positive gonadotrophs, particularly in the anterior part of the proximal pars distalis. This effect is considered on activation of the gonadotrophs. Cortisol administration induced pronounced degranulation and atrophy of the corticotrophs and this effect was strongest in the males. Neither the androgens nor the estrogens visibly affected the corticotrophs.

scholarly journals Histological study of pars tuberalis of the pituitary gland in local male buffaloes ″Bubalus bubalis

2010 ◽  
Vol 34 (2) ◽  
pp. 99-102
Author(s):  
Malallah H. B
Keyword(s):  
Pituitary Gland ◽  
Light Microscope ◽  
Blood Circulation ◽  
Histological Study ◽  
Cell Types ◽  
Bubalus Bubalis ◽  
Pars Tuberalis ◽  
Pars Distalis ◽  
Functional Importance ◽  
Histological Results

This study was carried out on the pituitary gland of eight male buffaloes 3-5 years old, examined under light microscope. The histological results revealed that the pars tuberalis contained four types of cells, not similar to any other cell types of the pars distalis. This finding and the location of the pars tuberalis at the gate of pars distalis which control the blood circulation give the pars tuberalis a special functional importance.

Cushing's Case XLV: Minnie G.

2002 ◽  
Vol 97 (1) ◽  
pp. 231-234 ◽  
Author(s):  
Giuseppe Lanzino ◽  
Niki F. Maartens ◽  
Edward R. Laws
Keyword(s):  
Pituitary Gland ◽  
Clinical Course ◽  
Clinical Manifestations ◽  
Low Grade ◽  
Content Type ◽  
Secondary Sexual Characteristics ◽  
Harvey Cushing ◽  
First Case ◽  
Sexual Characteristics ◽  
Fine Print

✓ A 23-year-old patient who was examined in 1910 by Harvey Cushing triggered his lifelong interest in the syndrome that bears his name. “Minnie G.,” as she became historically known, presented with a “… syndrome of painful obesity, hypertrichosis, and amenorrhea with overdevelopment of secondary sexual characteristics accompanying a low grade of hydrocephalus and increased cerebral tension.” This case stimulated Harvey Cushing's inquisitive mind and sparked an interest that 20 years later culminated in his seminal report, “The basophil adenomas of the pituitary gland and their clinical manifestations (pituitary basophilism).” In this classic work, Cushing reported in detail the cases of two patients encountered from his own practice and 10 similar cases collected from the literature. Minnie G. was the first case that Cushing reported. The clinical course of that case is briefly reviewed in this article.

Ultrastructure of the eta cells in the pituitary gland of adult migratory sockeye salmon (Oncorhynchus nerka)

1969 ◽  
Vol 47 (5) ◽  
pp. 937-941 ◽  
Author(s):  
H. Cook ◽  
A. P. van Overbeeke
Keyword(s):  
Endoplasmic Reticulum ◽  
Pituitary Gland ◽  
Sockeye Salmon ◽  
Secretory Granules ◽  
Oncorhynchus Nerka ◽  
Pars Distalis ◽  
Cell Type ◽  
Spawning Grounds ◽  
Predominant Cell Type ◽  
Rostral Pars Distalis

In the rostral pars distalis of the adult migratory sockeye salmon (Oncorhynchus nerka), most of the cells are arranged in follicles. The predominant cell type, the eta cell, contains secretory granules of 175–300 mμ in diameter; its endoplasmic reticulum shows a conspicuous lamellar organization. These cells undergo only slight changes as the fish migrate from the ocean to the spawning grounds. The findings are discussed in relation to the function of prolactin in euryhaline teleosts.

Primary Amenorrhoea with Pituitary Dwarfism: A rare case report

2016 ◽  
Vol 2 (2) ◽  
pp. 145-147
Author(s):  
Siva S ◽  
Divya Gopineni ◽  
Shafi P ◽  
Chandra Sekhar
Keyword(s):  
Pituitary Gland ◽  
General Medicine ◽  
Pituitary Hormones ◽  
Thyroid Stimulating Hormone ◽  
Primary Amenorrhea ◽  
Pituitary Dwarfism ◽  
Primary Amenorrhoea ◽  
Sexual Characteristics ◽  
Loss Of Appetite ◽  
Secondary Sexual

Females with pituitary dwarfism and a multiple deficiency of pituitary hormones show ovarian dysfunction due to hypogonadotropism. Primary amenorrhea can be diagnosed if a patient has normal secondary sexual characteristics but no menarche by 16 years of age. A 16 year-old female patient admitted in general medicine department with chief complaints of shortness of breath on exertion since 15 days, swelling of both legs since 10 days, loss of weight since 5 months, loss of appetite since 3 months, history of pain during swallowing. Pelvis scan examination reveals that uterus measures 3.2×0.5×0.5cm; uterus is hypo plastic, ovaries not visualized. Patient parents reveled that from patient birth to 11years of age her growth and other developments were normal, after that her growth is stopped and no changes were observed in development since 5 years. Patient has hypothyroidism so pituitary gland make an important role to maintain hormone levels, pituitary gland produces thyroid stimulating hormone (TSH) which stimulates thyroid gland to produce thyroid hormones. Primary Amenorrhea, short stature and poorly developed secondary sexual characters which could have been contributed and should be subjected for karyotyping. This type of Pituitary Dwarfism is very difficult to manage.

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