Pangenomic Classification of Pituitary Neuroendocrine Tumors

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白黎芦醇对GH3细胞增殖和PRL合成的影响

目的 探讨白黎芦醇对垂体腺瘤GH3细胞增殖和泌乳素合成的影响，及其对雌激素的拮抗作用。方法 在无血清无酚红的培养条件下，白黎芦醇单独或与雌二醇联合作用于GH3细胞，用MTT法测定细胞增殖，用免疫荧光法、RT-PCR和Western印迹法测定泌乳素的表达情况。结果 白黎芦醇对GH3细胞增殖具有刺激和抑制双相作用，呈时间一剂量依赖性。并且白黎芦醇使GH3细胞中PRL阳性细胞比例下降。同时，白黎芦醇抑制泌乳素的合成。白黎芦醇对雌二醇诱发的细胞增殖和泌乳素合成均有拮抗作用．但对泌乳素合成的拮抗作用较强，而雌二醇刺激细胞增殖作用较其诱发泌乳素合成作用强。结论 白黎芦醇对GH3细胞增殖和泌乳素合成均有抑制作用，从两方面发挥着抗肿瘤作用。     

Is pregnancy the best treatment for hyperprolactinaemia?

This paper reports the changes in prolactin levels after 12 spontaneous and 52 induced pregnancies in 54 women with unambiguous hyperprolactinaemia (median plasma prolactin levels 67.5 ng/ml, range 40-400). Twenty-three of the patients showed radiological evidence of prolactinoma. The pregnancies were induced in 37 patients by bromocriptine, in nine by metergoline, in two by lisuride and in four by other treatments. Of the 64 pregnancies, 16 ended in spontaneous abortion, while 48 went to term. Follow-up was continued for at least 6 months after delivery or until the end of lactation. In a control group of 32 hyperprolactinaemic women (median prolactin 70 ng/ml, range 40-400) not wishing to become pregnant, prolactin changes were similarly registered over a mean period of 15 months without any treatment (range 6-38 months). After pregnancy, a significant downward trend of plasma prolactin was observed in the puerperal women with a 'normalization' rate of 17%. No changes were observed in the 32 controls who did not become pregnant.     

Primary aspergillosis of the sphenoid sinus with pituitary invasion – a rare differential diagnosis of sellar lesions

Summary Aspergillosis belongs to the group of mycotic diseases of paranasal sinuses. The invasive forms, and particularly the fulminant forms, are potentially fatal. Isolated aspergillosis of the sphenoid sinus or the clivus is a difficult diagnosis, since the often misleading clinical manifestations of this rare disease develop late. These patients become apparent by neurological signs such as cavernous sinus syndrome, pseudotumor of the pituitary or the orbit. Diagnosis is often made intra-operatively or on histological examination. We report a case of invasive aspergillosis uniquely involving the sellar area revealed by clinical features suggesting a pseudotumor of the pituitary. Although such lesions are almost always seen in immune suppressed subjects, in our case, the patient was immune competent and had no past history of sinusitis. The question of whether, and when to perform limited or extensive surgery remains an issue for discussion, owing to the rarity of this disease honed by lack of experience. It depends on several factors: the kind of disease, the immunity, the subtype of invasive fungal sinusitis and the degree of tissue invasion.     

The role of the le fort I maxillotomy in the management of incompletely resected pituitary macroadenomas.

Objective: The options available for the treatment of a nonsecreting pituitary macroadenoma that has been incompletely resected include reoperation, fractionated radiation therapy, and radiosurgery. Reoperation in this setting may be hindered by the same obstacles that prevented a complete resection during the initial surgical procedure, and should prompt consideration of an alternate approach or exposure. Methods: Between January 1998 and December 2003, 10 consecutive patients were referred to the Department of Neurosurgery at the University of Texas Southwestern Medical Center for the evaluation of a nonsecreting pituitary macroadenoma that measured 3 cm or greater in diameter despite having undergone an attempt at a complete resection elsewhere. Each of these patients was reoperated using a Le Fort I maxillotomy to enhance the exposure provided by a traditional transsphenoidal approach. Results: A total or near total (> 95%) resection was achieved in each case. One patient required reoperation for the repositioning of a fat graft to treat a cerebrospinal fluid fistula and one patient experienced a worsening of anterior pituitary function postoperatively. Five patients noted improved vision and no patient experienced further visual loss. Three patients have required subsequent treatment of small foci of recurrent or progressing tumor with stereotactic radiation therapy. No patient has received fractionated radiation therapy. Conclusion: The added exposure provided by a Le Fort I maxillotomy facilitates the resection of pituitary macroadenomas that have been incompletely resected by a traditional transnasal, trans-sphenoidal approach.     

In vivo Regulation of Prolactin Gene Expression in the Male Rat: Role of Sex Steroids and Dopamine

The influence of sex steroids and the dopaminergic system on the in vivo modulation of prolactin (PRL) mRNA levels was investigated by quantitative in situ hybridization in the male rat anterior pituitary gland. In situ hybridization was performed using a [³⁵S]-labeled cDNA probe encoding PRL. Orchiectomy performed 14 days earlier did not modify PRL mRNA levels. In orchiectomized rats treatment with the dopaminergic agonist bromocriptine for 14 days decreased PRL mRNA levels by 30%, while in intact animals the same treatment did not induce any changes in PRL mRNA levels. Administration of the dopamine D₂ receptor antagonist haloperidol in both intact and orchiectomized rats induced a 4-fold increase in mRNA levels. Administration of dihydrotestosterone to orchiectomized animals which had been treated or not with haloperidol or bromocriptine did not modify PRL mRNA levels. In orchiectomized animals administration of 17ß-estradiol (0.25 μg twice daily) for 14 days caused a 4-fold increase in amounts of PRL mRNA. Administration of bromocriptine to 17ß-estradiol-treated animals induced a 15% decrease of PRL mRNA levels compared to those obtained by 17ß-estradiol administered alone. The concomitant administration of 17ß-estradiol and haloperidol resulted in a 50% increase in PRL mRNA levels compared to those measured in animals treated with haloperidol alone. The present results clearly demonstrate that in vivo estrogen as well as dopamine-mediated mechanisms play a regulatory role in PRL mRNA levels in the male rat.     

Pituitary adenomas: Trans‐sphenoidal experience of 300 cases

Objective: The main aim of the present study was to examine the effectiveness and complication rate of the 1 cm right‐sided unilateral sublabial trans‐sphenoidal surgery for patients with pituitary adenoma equal to or greater than 5 mm in diameter. Method: A total of 350 patients were surgically treated for pituitary adenomas between December 1999 and December 2003 in an academic neurosurgical unit in China. Three hundred patients (86%) were treated with the 1‐cm right‐sided unilateral sublabial trans‐sphenoidal approach. The mean age of patients was 43 years (range 10–78 years) and female patients accounted for 59% of the total. One hundred and ninety‐six (64%) patients had functioning endocrine tumours and 104 (36%) patients had non‐functioning tumours or macroadenomas. Tumours which were outside this simple and basic classification were excluded from the study. Results: There were no operative mortalities. One patient developed hypopituitarism and 16 (5%) developed transient diabetes insipidus that required pituitrin treatment. The remission rate for macroadenoma was 85% and that for microadenoma was 98.5% during a medium term follow‐up of 1–5 years. One hundred and fifteen patients had prolactin secreting tumours and 90.4% achieved endocrine remission. Fifty‐six patients had growth hormone secreting tumours and 75.4% achieved endocrine remission. Preoperatively, one hundred and fifty‐one patients presented with visual impairment and 148 (98%) achieved a documented improvement in visual acuity. The mean duration of hospital stay was 4 days (range 3–7 days). Conclusion: This minimally invasive trans‐sphenoidal surgery for pituitary adenomas could be used as the primary treatment for small pituitary tumours. The effectiveness of the tumour removal and low morbidity rate compare favourably with the conventional sublabial approach as well as the more recently developed endoscopic endonasal approaches.     

Acetylcholine Synthesis in a Primary Culture of Porcine Intermediate Lobe Cells

Previous pharmacological studies with the pituitary gland have suggested that acetylcholine (ACh) might be involved in the regulation of intermediate lobe (IL) function. Whether ACh is endogenous to the IL cells or provided from an extrinsic source is unclear. The present experiments tested the possibility that the endocrine cells of the IL may be a source of ACh by measuring certain cholinergic markers in a primary culture of dissociated porcine cells. The endogenous ACh content was readily measurable in both the freshly dissociated IL cells and in 2- or 4-day primary cultures. Choline acetyltransferase activity was also measurable in the freshly dissociated and cultured IL cells and was reduced by 53% in the presence of a specific inhibitor, napthylvinylpyridine (50 μM). IL cells incubated in the presence of [¹⁴C]choline (1 μM) were able to synthesize [¹⁴C]ACh and the accumulation of the new ACh was inhibited by hemicholinium-3 (30 μM), a competitive inhibitor of high affinity choline uptake at cholinergic nerve terminals. In conclusion, these results demonstrate that the endocrine cells of the IL are capable of synthesizing and storing ACh.