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Journal Article 2013; 34(4): 302-308 PubMed PMID: 23803874 Citation  Keywords:  Animals, Cells, Cultured, Chromatography, Ion Exchange, Female, GABA Agents:pharmacology, Gonadotrophs:drug effects, Gonadotropin-Releasing Hormone:pharmacology, Inositol 1,4,5-Trisphosphate:biosynthesis, Luteinizing Hormone:drug effects, Pituitary Gland,.   

OBJECTIVE: Mechanism(s) responsible for VPA-induced effects on reproductive axis activity are not fully recognized. Previously we reported that VPA suppressed only GnRH-stimulated but not the basal LH release from rat anterior pituitary (AP) cells in vitro. Since the inhibitory effect of VPA was exerted only in GnRH-activated cells, potential VPA impact on GnRH-R-coupled IP3/PKC signaling could not be excluded. In this study the effect of VPA on IPs synthesis in non-stimulated and GnRH-treated rat AP cells was examined.

MATERIAL AND METHODS: In the first experiment 5 × 105 cells/ml were incubated for 3h with VPA (10 nM-10 μM), PMA (100 nM), GnRH (100 nM), PMA (100 nM) + VPA (10 nM-10 μM), GnRH (100 nM) + VPA (10 nM-10 μM). In the second experiment cells were preincubated for 24h with 1μCi myo-[23 H]-inositol, then for 30 min with 10 mM LiCl and finally for 3hr with GnRH (100 nM) VPA (1 μM, 10 μM), GnRH (100 nM) + VPA (1 μM, 10 μM). LH concentration was measured by RIA and intracellular IPs accumulation by ion-exchange chromatography analysis.

RESULTS: VPA diminished GnRH-stimulated LH release without affecting PMA-induced LH release at any dose tested. Moreover, VPA-induced increase of IPs accumulation occurred in both non-stimulated and GnRH-treated cells and intensity of cellular response was similar in both groups.

CONCLUSION: VPA affects IP3/PKC pathway activity through its up-regulatory effect on IPs synthesis in AP cells. VPA-induced inhibition of GnRH-stimulated LH release from gonadotrope cells appears to be the result of still unrecognized cellular mechanism....

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Case Reports 2013; 34(4): 275-277 PubMed PMID: 23803868 Citation  Keywords:  Adolescent, Antineoplastic Agents:therapeutic use, Ergolines:therapeutic use, Female, Humans, Induction Chemotherapy:methods, Menarche, Pituitary Neoplasms:drug therapy, Prolactinoma:drug therapy, Tumor Burden,.   

: Giant prolactinomas are extremely rare in the pediatric population. We describe the case of a giant prolactinoma in a girl aged 14 years and 9 months old presented with delayed puberty. Medical treatment with dopamine agonist cabergoline resulted in a rapid normalization of prolactine levels and an impressive shrinkage and liquefaction of the mass as illustrated in serial MRIs. The therapeutic dilemma regarding the type of treatment (medical versus surgical) has now been replaced by the dilemma regarding the optimal treatment strategy and duration. Initial, rather optimistic, estimations regarding the probability of treatment discontinuation without increased relapsing risk have now been replaced by guidelines with more strict criteria for selecting candidates for treatment discontinuation....

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Journal Article 2013; 34(3): 207-211 PubMed PMID: 23685418 Citation  Keywords:  Adult, Cohort Studies, Female, Follow-Up Studies, Galactorrhea:diagnosis, Humans, Hyperprolactinemia:diagnosis, Middle Aged, Pituitary Gland, Anterior:physiology, Pituitary Neoplasms:diagnosis, Pregnancy, Pregnancy Outcome, Prolactin:blood, Prolactinoma:d.   

OBJECTIVES: To determine the frequency of macroprolactinemia in a cohort of hyperprolactinemic women, describing 1) the association of macroprolactinemia with clinical variables and morphological changes in the pituitary gland and 2) clinical status and prolactin levels after 10 years of follow-up.

DESIGN: Blood samples were obtained from 32 patients for hormonal assessment. Treatment with cabergoline or bromocriptine was interrupted 3 months before the determination of serum prolactin and macroprolactin. Macroprolactin was measured using the polyethylene glycol (PEG) precipitation method. Computed tomography was performed in all patients.

RESULTS: The frequency of macroprolactinemia was 28.1%. In 19 patients prolactin remained elevated (persistent hyperprolactinemia). In 13, prolactin returned to normal (former hyperprolactinemia). Nine patients with PEG recovery between 40 and 50%, and the only two macroprolactinemic patients with previous hyperprolactinemia were excluded from the analysis of clinical outcomes. Only one of seven macroprolactinemic patients had an abnormal pituitary image (empty sella). None had galactorrhea.

MAIN FINDINGS: Classic symptoms of hyperprolactinemia and abnormal imaging findings are not common in patients in whom macroprolactin is the predominant form of PRL.

CONCLUSIONS: Women with hyperprolactinemia, especially if asymptomatic, should be routinely screened for macroprolactinemia. Macroprolactinemia remains stable in the long term....

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Journal Article 2013; 34(2): 143-153 PubMed PMID: 23645312 Citation  Keywords:  Animals, Circadian Rhythm:physiology, Male, Photoperiod, Pineal Gland:metabolism, Pituitary Gland:metabolism, Rats, Rats, Sprague-Dawley, Seasons, Testis:metabolism, Testosterone:metabolism,.   

BACKGROUND: Photoperiodic changes mediate certain physiological or pathological alterations in organisms. Solstices represent either the longest or shortest photoperiod of a year.

OBJECTIVES: Intact and pinealectomized rats were used to investigate the potential changes of reproductive hormones in the hypothalamus-pituitary-testis (HPT) axis including GnRH, FSH, LH, testosterone and melatonin, and their receptors at summer solstice (SS) and winter solstices (WS).

METHODS: The levels of reproductive hormones in HPT axis and the binding characteristics of their receptors were examined using radioimmunoassay and radioreceptor assay techniques, respectively.

RESULTS: The results indicate that in the intact male rat, GnRH, LH and testosterone are higher at the SS than at the WS. However, FSH exhibited no significant seasonal changes. In the testis, Bmax and Kd of LH receptors are higher at the WS than at the SS while those of FSH receptors are higher at the SS than at the WS. In addition, the melatonin in HPT axis appeared significant differences between WS and SS. Bmax and Kd of melatonin receptors in the hypothalamus and pituitary also showed higher at the WS than at the SS. Moreover, reproductive hormone production lost their seasonal rhythms after pinealectomy.

CONCLUSION: The most important discovery in this study is that we first reported that pinealectomy had profound effects on the binding characteristics of melatonin with its subtype receptors. Especially at the hypothalamus, the dominated melatonin receptors shifted from MT1 to MT2 after pinealectomy at the two solstices....

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Case Reports 2013; 34(2): 102-106 PubMed PMID: 23645305 Citation  Keywords:  Autoimmune Diseases:diagnosis, Empty Sella Syndrome:diagnosis, Female, Glucocorticoids:therapeutic use, Humans, Hypopituitarism:diagnosis, Inflammation:pathology, Magnetic Resonance Imaging:methods, Middle Aged, Pituitary Gland:pathology, Treatment Outcom.   

: Autoimmune hypophysitis (AH) is commonly believed to be a rare chronic inflammatory condition of the pituitary gland. In clinical practice, however, the disease is often seen indeed. It typically presents with hypopituitarism and pituitary mass found by MRI. We report here unusual presentations of two females with AH followed by empty sella syndrome. The two females, aged at 64 and 57-years-old, presented with anterior pituitary dysfunction, diplopia and diabetes insipidus. By MRI the two patients shared the common characteristics with diffuse homogenous contrast enhancement of the gland and increased stalk thickness. After a long period treatment with glucocorticoids, empty sella was eventually detected by MRI....

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Case Reports 2012; 33(8): 765-768 PubMed PMID: 23391974 Citation  Keywords:  Adenoma:surgery, Adult, Angiography, Digital Subtraction, Female, Humans, Male, Middle Aged, Neuronavigation:methods, Neurosurgical Procedures:methods, Oculomotor Nerve Diseases:surgery, Pituitary Neoplasms:surgery, Sella Turcica:diagnostic imaging, Sphen.   

: A concha non-pneumatized sphenoid is considered to be a contraindication for the transsphenoidal resection of a pituitary adenoma. Specifically, this anatomical variation makes it difficult to approach the sella turcica. However, in this report, an intra-operative navigational system was used as a guide to access the sella through the sphenoid sinus. This procedure was found to be both reasonable and safe....

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Case Reports 2012; 33(6): 574-578 PubMed PMID: 23160230 Citation  Keywords:  Biopsy, Brain Abscess:complications, Diagnosis, Differential, Humans, Hypopituitarism:diagnosis, Magnetic Resonance Imaging, Male, Middle Aged, Pituitary Gland:pathology, Sella Turcica:pathology,.   

: Pituitary abscess is a rare condition. Here, we present the case of a young male patient who was initially found to have a pituitary lesion following the diagnosis of panhypopituitarism. Two years later, he presented with severe headache and was subsequently diagnosed intraoperatively with pituitary abscess. At a follow-up of 6 years after surgery, the patient was continuing to do very well. We discuss the differential diagnosis and demonstrate the evolution of the pituitary lesion on magnetic resonance imaging at four different time points: at the time of the detection of the initial lesion; two years later at the time of the diagnosis of the pituitary abscess; at 7 weeks post operatively; and finally after six years from the pituitary surgery....

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Case Reports 2012; 33(5): 483-488 PubMed PMID: 23090264 Citation  Keywords:  Adult, Critical Illness, Dopamine Agonists:therapeutic use, Female, Humans, Neurosurgical Procedures:methods, Pituitary Apoplexy:drug therapy, Pituitary Neoplasms:drug therapy, Pregnancy, Pregnancy Complications:drug therapy, Prolactinoma:drug therapy, Sp.   

: Prolactinoma is the most common secreting pituitary adenoma. It is typically diagnosed in women of reproductive age and is common cause of infertility. Currently the treatment of choice is pharmacotherapy with dopamine agonists, whereas surgical treatment is reserved for a selected group of patients. Pituitary-tumor apoplexy is a rare, life-threatening condition associated with significant morbidity and mortality. The authors present the case of a 25-year-old woman with prolactinoma treated with dopamine agonist. In course of such a treatment the patient became pregnant. The bromocriptine was gradually withdrawn. In the 14th week of pregnancy she was admitted for symptoms suggesting pituitary tumor apoplexy. The treatment with bromocriptine was reinitiated. In the 20th week of pregnancy further deterioration of the patient's neurological condition and visual-field abnormalities were observed. The patient was qualified for surgical treatment - selective transsphenoidal adenomectomy. The successful surgery led to improvement of neurological condition. The early postoperative PRL level decreased significantly and hormonal function of the pituitary was preserved. The pregnancy ended in 38th week with a caesarean section. Endocrinological evaluation conducted after the uneventful delivery confirmed normal function of the pituitary. Magnetic resonance imaging (MRI) did not reveal tumor re-growth. The patient is kept under constant medical care. In this case study the authors discussed therapeutic management and reviewed literature regarding gestational pituitary-tumor apoplexy with particular emphasis on surgical treatment....

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