MR-appearance of the pituitary gland before and after resection of pituitary macroadenomas

ABSTRACT Destruction of the thyroid gland in the mouse induces proliferation of pituitary thyrotropes. This phenomenon was studied quantitatively with 3H-thymidine, before and after oral administration of thyroxine. The frequency of radioactive cells in the intact animal is 3.4 per 10 000 pituitary cells. This value rises to 19.6, 18.4 and 56.0 four, eight, and twelve months after thyroidectomy, respectively. All these increased values are brought back to normal levels after 5 to 10 days of thyroxine treatment. Thus, the intense proliferation of pituitary thyrotropes following thyroidectomy is still responsive to the homeostatic action of thyroxine.

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Effect of estradiol on the secretion of LH in the GnRH-pretreated rat after treatment with the GnRH-antagonist, Org 30093

Acta Endocrinologica ◽

10.1530/acta.0.1190582 ◽

1988 ◽

Vol 119 (4) ◽

pp. 582-588

Author(s):

G. A. Schuiling ◽

N. Valkhof ◽

T. R. Koiter

Keyword(s):

Pituitary Gland ◽

Gnrh Antagonist ◽

Plasma Concentrations ◽

Estradiol Benzoate ◽

The Other ◽

Gnrh Analogue ◽

Before And After ◽

Pituitary Glands ◽

Lh Secretion

Abstract. LH responses induced in the long-term ovariectomized rat by GnRH or GnRH agonistic analogue are augmented by E2. The augmentation by E2 does not occur during, but after termination of GnRH pretreatment. In this study it was investigated whether the augmenting effect of E2 develops also in the GnRH-pretreated rat when the animals were treated with GnRH antagonistic analogue. Two weeks after ovariectomy rats were treated for 10 days with 250 ng GnRH/h (GnRH-rats), released by sc implanted osmotic minipumps. Control rats received a Silastic 'sham pump'. Rats were simultaneously treated with solvent (oil) or estradiol benzoate (EB, 3 μg, sc). Each group of rats was divided into two subgroups, one receiving solvent, the other the GnRH antagonist, Org 30093 (ANT, 100 μg/injection) on 3 consecutive days. In Experiment 1, the pituitary LH content and the LH secretion following stimulation with the agonistic GnRH analogue buserelin, were measured, in Experiment 2, the plasma concentrations of LH before and after cessation of ANT treatment. The effects of treatment with GnRH, EB and ANT were studied on the basis of 1) the height of the maximal LH response and 2) the halfmaximally effective dose (ed 50) of buserelin. Experiment 1 revealed that GnRH depleted the pitutiary gland to about 42% of its original LH content. In EB-treated GnRH-rats the depletion was even stronger (to 14%). After ANT treatment, the pituitary glands of the GnRH-rats were (partly) repleted (oil: to 65%; EB: to 31%). ANT and EB had no effect on the pituitary LH content in control rats. EB increased the maximal LH response in control rats but not in GnRH-rats. ANT increased the maximal LH response to buserelin in oil-injected control rats as well as in oil- and EB-treated GnRH-rats. In these latter two groups, the increase of the maximal LH response was equally large. However, there was an effect of EB on the ed 50 of buserelin during ANT treatment, the pituitary gland of the EB-treated GnRH-rats had become more sensitive to GnRH. Experiment 2 revealed that GnRH pretreatment reduced the plasma LH concentrations to about 49% of the control levels. EB and ANT, too, lowered the plasma LH concentrations (to about 25%). Neither EB nor ANT, alone or in combination, changed the plasma LH concentrations in GnRH-rats. After cessation of ANT treatment, the plasma LH levels of the oil-injected control rats slowly returned to pretreatment levels, but those of the EB-treated control rats remained suppressed. In the GnRH-rats the reverse was seen: after cessation of ANT treatment, peaks of LH appeared in the plasma of the EB-treated rats, but not in the oil-injected. It is concluded that 1) treatment with ANT is not fully equivalent to termination of GnRH administration because it antagonizes the effects of GnRH only in part: 2) ANT has an intrinsic augmenting effect on the pituitary GnRH-responsiveness, and 3) owing to E2-induced sensitization of the pituitary gland, peaks of LH appear in the plasma of GnRH-rats but not of control rats after termination of ANT treatment.

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A COMMON PITUITARY AUTOANTIBODY IN TWO PATIENTS WITH IMMUNE CHECKPOINT INHIBITOR-MEDIATED HYPOPHYSITIS: ZCCHC8

AACE Clinical Case Reports ◽

10.4158/accr-2019-0585 ◽

2020 ◽

Vol 6 (4) ◽

pp. e151-e160

Author(s):

Amanda Leiter ◽

Sacha Gnjatic ◽

Mary Fowkes ◽

Seunghee Kim-Schulze ◽

Ilaria Laface ◽

...

Keyword(s):

Pituitary Gland ◽

Immune Checkpoint ◽

Immune Checkpoint Inhibitor ◽

Cytotoxic T Lymphocyte ◽

Checkpoint Inhibitor ◽

Severe Fatigue ◽

Metastatic Urothelial Cancer ◽

Before And After ◽

Serial Samples ◽

First Time

Objective: Hypophysitis is an increasingly recognized adverse effect of immune checkpoint inhibitor (ICI) therapy for malignancy. However, the mechanisms through which ICIs induce hypophysitis are largely unknown. We aim to describe 2 cases of ICI-mediated hypophysitis and perform autoantibody profiling on serial samples from these patients to determine if common autoantibodies could be identified. Methods: We describe 2 cases of patients with metastatic urothelial cancer who received ICI therapy and subsequently developed severe fatigue, prompting a hormonal workup consistent with hypopituitarism. Patient 1 received the ICI ipilimumab (anti-cytotoxic T-lymphocyte-associated protein 4) and patient 2 received the ICI pembrolizumab (anti-programmed cell death protein 1). Both patients had serial seromic immune biomarker profiling using high-density protein arrays before and after developing hypophysitis. Once a common autoantibody was found, zinc finger CCHC-type containing 8 (ZCCHC8), we used immunohistochemistry to assess its presence in pituitary tissue. Results: Of a limited number of increased autoantibodies detected, those to ZCCHC8 were the only common antibodies to increase at least 3-fold post-hypophysitis in both patients. Using immunohistochemistry staining, we show for the first time that ZCCHC8 is expressed in pituitary gland tissue. Conclusion: Seromic profiling identified a common autoantibody, ZCCHC8, in 2 patients who developed hypophysitis on ICI therapy, and other serial autoantibody increases in each patient. These findings warrant validation in other cohorts to determine if the response is to self or tumor antigen, and may reveal novel insights into pituitary gland physiology and the pathogenesis of ICI-mediated hypophysitis.

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THE INFLUENCE OF HYPOPHYSECTOMY ON NSILA CONCENTRATIONS IN THE DOG: EVIDENCE FOR PARTIALLY PITUITARY-INDEPENDENT REGULATION

Acta Endocrinologica ◽

10.1530/acta.0.0860498 ◽

1977 ◽

Vol 86 (3) ◽

pp. 498-503 ◽

Cited By ~ 4

Author(s):

J. E. Eigenmann ◽

M. Becker ◽

B. Kammermann ◽

J. Zapf ◽

W. Leemann ◽

...

Keyword(s):

Growth Hormone ◽

Thyroid Hormone ◽

Pituitary Gland ◽

Normal Level ◽

Binding Assay ◽

Serum Samples ◽

Protein Binding Assay ◽

Before And After ◽

Low Levels ◽

Insulin Like Activity

ABSTRACT Non-suppressible insulin-like activity (NSILA) was determined in 5 dogs before and after hypophysectomy. All NSILA determinations were carried out on serum samples after acidic Sephadex G-50 chromatography by two different assay systems, i. e. a bioassay and a protein binding assay. The levels of NSILA decreased significantly after hypophysectomy and returned to near normal levels after 2 weeks. T3−, T4− and cortisol levels were drastically reduced during the entire period of the experiment. Several GH determinations after hypophysectomy revealed very low levels. Insulin-induced hypoglycaemia failed to provoke a rise of GH levels as late as 4 months after hypophysectomy. These findings indicate that: 1) The pituitary gland cannot be the site of synthesis of NSILA. 2) NSILA concentrations in the dog are maintained at a near normal level in the presence of very low growth hormone and thyroid hormone concentrations, so that these latter hormones do not appear to be the only regulatory factors concerned in NSILA synthesis.

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Isolated ACTH deficiency accompanied by 'primary hypothyroidism' and hyperprolactinaemia

Acta Endocrinologica ◽

10.1530/acta.0.1040397 ◽

1983 ◽

Vol 104 (4) ◽

pp. 397-401 ◽

Cited By ~ 10

Author(s):

Tadayoshi Yoshida ◽

Tetsuya Arai ◽

Jinpei Sugano ◽

Hiroshi Yarita ◽

Hideo Yanagisawa

Keyword(s):

Pituitary Gland ◽

Primary Hypothyroidism ◽

Hormonal Changes ◽

Plasma Acth ◽

Isolated Acth Deficiency ◽

Acth Deficiency ◽

Corticotrophin Releasing Factor ◽

Lysine Vasopressin ◽

Before And After

Abstract. A 55 year old man with isolated ACTH deficiency is reported. The lesion would appear to be located in the pituitary gland since plasma ACTH and cortisol did not respond to lysine vasopressin and corticotrophin releasing factor (CRF). A fall in T4, a rise in basal values of TSH, prolactin (Prl), LH and FSH, excessive responses of TSH and Prl to TRH, and hyperreactive responses of LH and FSH to LRH were observed. These hormonal changes were examined before and after administration of cortisol. The abnormality in these hormones might be caused by deficiency of long-term glucocorticoid.

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The Regional Oxygen Saturation of Pituitary Adenomas Is Lower than That of the Pituitary Gland: Microspectrophotometric Study with Potential Clinical Implications

Neurosurgery ◽

10.1227/01.neu.0000083604.09901.f6 ◽

2003 ◽

Vol 53 (4) ◽

pp. 880-886 ◽

Cited By ~ 12

Author(s):

Rudolf A. Kristof ◽

Ales F. Aliashkevich ◽

Volkmar Hans ◽

Dorothee Haun ◽

Bernhard Meyer ◽

...

Keyword(s):

Standard Deviation ◽

Oxygen Saturation ◽

Pituitary Gland ◽

Pituitary Adenomas ◽

Anterior Pituitary ◽

Posterior Pituitary ◽

Pituitary Tissue ◽

Adenoma Tissue ◽

Posterior Pituitary Lobe ◽

Pituitary Macroadenomas

Abstract OBJECTIVE To study the regional oxygen saturation (rSO2) of pituitary adenomas, in comparison with that of the pituitary gland. METHODS Microspectrophotometric (MSP) measurements of rSO2 in adenomas and pituitary tissue were performed for a series of patients undergoing first-time transsphenoidal pituitary adenoma surgery, in a standardized anesthesia setting. The areas of measured tissue were sampled for histopathological and immunohistochemical (CD34 and CD45) assessments. The results of MSP measurements were compared with the results of the histopathological and immunohistochemical assessments. RESULTS Thirty-six MSP measurements and tissue samples were obtained among 22 patients with pituitary macroadenomas, including 14 from adenoma tissue, 17 from the anterior pituitary lobe, and 5 from the posterior pituitary lobe. The rSO2 of adenoma tissue (mean ± standard deviation, 43.3 ± 23.2%) was statistically significantly (P = 0.001) lower than the values for the anterior pituitary lobe (mean ± standard deviation, 71.8 ± 18.3%) and posterior pituitary lobe (mean ± standard deviation, 74.9 ± 4.8%). The difference between the rSO2 values for the anterior pituitary lobe and posterior pituitary lobe was not significant. There were no statistically significant differences in microvessel density (as assessed with CD34 staining) or lymphocyte density (as assessed with CD45 staining) among the three tissue types. CONCLUSION As assessed with MSP measurements, the rSO2 of adenoma tissue was significantly lower than that of the pituitary gland, indicating differences in their blood supply and/or metabolism in pituitary macroadenomas. Further studies are needed to determine whether MSP measurements can reliably facilitate intraoperative delineation of adenoma and pituitary tissue, in the effort to achieve complete tumor removal with minimal injury to pituitary tissue.

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