The present study reports a rare case of full-blown Cushing's disease several years after an episode of pituitary apoplexy. A 60 year-old woman complained of muscular weakness and generalized malaise. Ten years ago she had an episode of pituitary apoplexy. Diabetes mellitus was diagnosed at age 56, and thereafter she had been controlled her plasma glucose with diet therapy and oral hypoglycemic agents. She exhibited cushingoid feature of moon face and central obesity. Both plasma ACTH and serum cortisol levels were elevated to 170 pg/ml and 19.6 μg/dl, respectively. Dexamethasone suppression test showed that a large dose of 8 mg dexamethasone, but not a small dose of 2 mg, suppressed the pituitary-adrenocortical axis. CRH and methyrapone caused increases in plasma ACTH and serum cortisol levels. Brain T1-weighted magnetic resonance imaging depicted a low signal of pituitary tumor, which was not enhanced by gadolinium. The pituitary tumor was removed by transsphenoidal adenomectomy, and immunohistochemistry revealed an ACTH-producing adenoma. The evidence suggested the possibility that the two pituitary tumors with dormant period of several years were a recurrence of ACTH-producing tumors in the present patient.
Paragangliomas of the head and neck are uncommon neoplasms. They are usually benign, but tend to be locally invasive. Although surgical resection remains the definitive treatment, important issues about management arise when such lesions are inoperable. Beneficial effects of octreotide treatment have already been reported in a malign paraganglioma case. Here we report a 24 year old female with familial, bilateral, multiple paraganglioma in the head and neck region, who firstly presented with pulsatile tinnitus and hearing loss in her left ear. After embolization was performed, she underwent operation twice because of the gross tumor mass. No significant change in tumor size was determined after the operations, however there were no distant metastases. Although she experienced hypertension attacks, no hormonal overproduction was found in repeated measurements. As the tumor was unresectable, new alternative therapies were sought. Octreotide scintigraphy was positive in the tumoral tissue, so we began to treat her with somatostatin analogue octreotide. After a 16 month follow up period, an improvement of the performance status, the near normalisation of attacks and stabilization of tumor growth were achieved. However, in the last three visits, she began to experience symptoms more frequently and it had been necessary to increase the octreotide dose. She is now well and being followed up. In conclusion, the beneficial effects of octreotide treatment could be quantified by clinical, tumor and scintigraphic criteria. These data suggest that octreotide can be useful in the treatment of inoperable paragangliomas.
Overproduction of vascular endothelial growth factor (VEGF) following human chorionic gonadotropin (hCG) stimulation has been implicated as one of the causative factors in the development of ovarian hyperstimulation syndrome (OHSS). The objective of this study was to clarify the action of hCG and progesterone, one of the possible factors for OHSS, on VEGF production and gene expression using OHSS-model rats. A total of 40 immature female Wistar rats were stimulated with 10 IU of equine chorionic gonadotropin for four consecutive days from the 22nd to 25th day of life followed by subcutaneous injection of 30 IU of hCG on the 26th day of life. RU486 and progesterone were injected 24 h after the hCG injection. Tissues and blood samples were collected on the 28th day. hCG elicited VEGF production in the OHSS-model rat ovaries. Ovarian weights of the OHSS model rats were significantly increased through day 26 by the ovarian stimulation with single dose of 30 IU hCG. Addition of anti-progesterone RU486, which reduced the ovarian enlargement, attenuated VEGF production dose dependently whereas the VEGF gene expression was stable. In the lung and liver, neither hCG nor RU486 affected VEGF production and gene expression. These results suggested that progesterone regulates VEGF production at the post-transcriptional level in a tissue specific manner in the hyperstimulated ovary.
Parathyroid cancer is rare but relatively frequent in Japan compared to Western countries. Surgical parathyroidectomy is the primary choice for radical treatment of primary hyperparathyroidism (pHPT), hence it is important to distinguish malignant from benign tumor in the determination of surgical indication as well as method of operation. However, it is not easy to diagnose parathyroid cancer prior to operation. In the present study, we analyzed the background data, biochemical data and bone mineral density (BMD) of 131 patients with pHPT (111 benign and 20 malignant). BMD of the lumbar spine and mid-radius was measured by dual-energy X-ray absorptiometry. Serum levels of calcium, alkaline phosphatase (ALP), and parathyroid hormone (PTH) were significantly higher in malignant group compared to benign one. The extent of elevation of mid PTH seemed to be higher than that of intact PTH in malignant group. Age-, gender-, and race-adjusted BMD of distal one-third of radius was significantly decreased in malignant group compared to benign one, although that of lumbar spine was not significantly different between the two groups, indicating that osteopenia was marked in the region which was rich in cortical bone in malignant group. On the other hand, serum levels of calcium, ALP, and mid PTH as well as age were selected as predictors of malignancy in univariate logistic regression analysis, while serum level of intact PTH was not selected. In conclusion, radial BMD was lower in malignant group compared to benign one in pHPT. Serum levels of calcium, ALP and mid PTH were useful to predict malignancy of affected parathyroid glands in pHPT patients.
Nitric oxide has various biological activities including smooth muscle relaxation, anti-inflammatory activity, anti-coagulatory activity. As the human placenta is known to express nitric oxide synthases, this study investigated the possible effect of labor on the expression of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) in human placental tissues at term. Both eNOS and iNOS mRNA expression in placental tissues in labor were significantly higher than those in the amnion, chorion laeve, decidua vera and myometrium. The eNOS mRNA and protein expressions in placental tissues in labor (n = 12) were 1.6023 ± 0.1652 (eNOS/GAPDH, mean ± SEM) and 12.8 ± 1.3 arbitrary units (AU), respectively, which were similar to those not in labor (n = 10), 1.5806 ± 0.2042 (eNOS/GAPDH) and 11.4 ± 1.8 AU. The iNOS mRNA and protein expressions in the placental tissues in labor were 1.2831 ± 0.2436 (iNOS/GAPDH) and 10.7 ± 2.1 AU respectively, similar to those not in labor, 1.9254 ± 0.8004 (iNOS/GAPDH) and 13.3 ± 1.8 AU. The guanosine 3',5'-cyclic monophosphate (cGMP) cocentration in the placental tissues in labor was 23.6 ± 1.4 fmol/g wet tissue, similar to that not in labor, 26.1 ± 2.0 fmol/g wet tissue. These findings suggest that nitric oxide production in the human placenta is maintained during labor.
We have developed a new test for estimating the secretory capacity of parathyroid hormone (PTH) from the parathyroid gland. Sodium bicarbonate solution [8.4% (w/v); 35 ml/m2 body surface area] was infused for 2 min, and blood samples for the determination of plasma ionized calcium, plasma PTH (intact, midregion, carboxy-terminus) and related parameters were serially obtained. In 8 healthy volunteers, the mean (±SE) plasma ionized calcium fell promptly and significantly (from 1.21 ± 0.01 to 1.11 ± 0.01 mmol/L) after the sodium bicarbonate infusion. The mean (±SE) plasma intact PTH increased promptly and significantly, by more than four fold (42.3 ± 4.2 to 182.4 ± 34.7 pg/ml), and then gradually returned to basal levels. In patients with partial hypoparathyroidism who have detectable basal plasma levels of PTH, the absolute increment in PTH levels was much less, and in the plasma obtained from patients with complete hypoparathyroidism, absolutely no response was observed. Plasma obtained from patients diagnosed with primary hyperparathyroidism (parathyroid adenoma or hyperplasia) has high basal PTH levels. The response to the sodium bicarbonate infusion in these patients was markedly blunted (less than a two-fold increase in all cases examined). No significant adverse effects were observed during the procedure. Therefore, the sodium bicarbonate infusion test is a simple and sensitive method to stimulate PTH release, and is clinically useful for evaluating parathyroid gland function.
It is known that, under stress conditions the hypothalamo-pituitary-adrenal (HPA) axis is stimulated and catecholamine production is increased. Adrenomedullin (ADM) is a novel peptide that elicits a long-vasorelaxation, and participates in blood pressure regulation via different mechanisms. In the present study, we investigated the administration of ADM on tyrosine hydroxylase (TH) enzyme activity in cold exposed rats. Four groups of Sprague-Dawley rats were studied for their TH enzyme activity in the adrenal medulla and hypothalamus. In addition to measuring blood pressure in these rats, TH enzyme activity in both the adrenal medulla and hypothalamus were examined in four groups of Sprague-Dawley rats: animals exposed to room temperature and cold stress (8ºC, 48 h), and rats injected with ADM (1.0 nmol/kg, i.v.) alone and/or together with cold stress. TH activity was shown to be increased in cold treated groups and decreased in ADM and ADM + cold stress group. Our findings appear to suggest that external ADM application caused an opposite effect on the same system in rats, decreasing the activity of tyrosine hydroxylase (TH) enzyme activity. Furthermore, externally applied ADM was shown to produce its expected hypotensive effect in cold-stressed rats. Our results suggest that a possible explanation for the effects of ADM is that, the uptake of ADM under cold stress may effect TH activity in studied tissues.
Resistance to thyroid hormone (RTH) is caused mainly by mutations of the thyroid hormone receptor (TR) β gene. Although, in vitro, TRα1 and TRβ1 mutants exhibit similar dominant negative effects against wild-type TR, no TRα mutants have ever been identified in RTH patients. It has been postulated that mutations in TRα gene may be lethal, compensated completely by intact TRβ or associated with phenotypic manifestations different from RTH. To investigate the consequences of mutant TRα1 expression in vivo, we tried to generate two different lines of transgenic mice which express a strong or a weak dominant negative mutant TR α1, respectively. First, we expressed βF451X identified in a patient with severe RTH and αF397X, which has an identical C-terminal truncation and a similarly strong dominant negative potency to βF451X, under the control of human polypeptide chain elongation factor 1α promoter. Six βF451X-transgenic mice were born from 223 transferred embryos, giving a transgenic frequency of 2.7%. By contrast, expression of αF397X resulted in quite a low transgenic frequency with 0.39% of the transferred embryos bearing the transgene. Only three transgenic mice were born with no apparently overt abnormalities, of which one male produced F1 offspring. The transgenic progeny expressed αF397X in the testis but we did not succeed in generating transgenic mice expressing αF397X in multiple organs. To avoid toxic effects mediated by a strong dominant negative activity of mutant TRα1, we exchanged αF397X for αK389E, which has an identical missense mutation and a relatively weak transdominant potency as βK443E identified in a patient with mild RTH. When expressed by cytomegalovirus immediate early enhancer-chicken β-actin promoter, we did not succeed in creating αK389E-transgenic mice despite three independent transgene-injections. These findings define crucial in vivo functions of mutant TRα1s during mouse fetal development and suggest the possibility that the expression of a dominant negative mutant TRα1 in extensive tissues from the early embryonal stages might be lethal.
We have previously reported that the urine of patients with Cushing's syndrome, including pituitary adenoma cases and adrenal adenoma cases, consistently show a conspicuous peak in the chromatographical analysis of 17-ketosteroid fraction but not in the urine of control subjects. The substance emerges just before 11β-hydroxy-androsterone (11β-OH-A) in capillary gas chromatography. In the present study, we have identified an "unknown peak substance" observed in the urine of Cushing's syndrome patients using gas chromatography-mass spectrometry (GC/MS). Trimethylsilylether (TMS)-derivative of the substance was found to have a molecular weight (MW) of 448, which is similar to that of 11-OH-A (MW: 450). From these findings, we hypothesized that the substance had the structure of a C-19 steroid with two hydroxyl groups at positions C-3 and C-11, one keto-group at C-17 and a double bond between C-4 and C-5 of the A ring. We hypothesized that the unknown peak substance was 3α,11β-dihydroxy-4-androsten-17-one (3α,11β-DH-A). To confirm this speculation we synthesized 3α,11β-DH-A and compared the elution pattern of it with that of the "unknown peak substance" using GC and GC/MS. We found that both substances were indistinguishable by GC and GC/MS analysis. These results suggest that the unknown substance observed in the urine of patients with Cushing's syndrome is 3α,11β-DH-A.
Oxytocin receptor (OTR) mRNA levels in the uterus dramatically increase in the near term human and rat. Estrogen is believed to be a potent stimulator of OTR mRNA expression. However, estrogen does not stimulate rat OTR mRNA expression on day 18 of pregnancy or in progesterone-treated rats. Thus, the regulation of uterine responsiveness to estrogen in the near term rat appears to be an important mediator of estrogen action. To determine the effect of altering uterine responsiveness to estrogen on OTR induction, uterine ERα and ER β mRNA levels were examined by competitive RT-PCR in pregnant and parturient rats, progesterone-treated ovariectomized (OVX) virgin rats and OVX pregnant rats. In pregnant and parturient rats, OTR mRNA levels were highest at 2200-2230 h on day 21 of pregnancy (P21pm) and during labor when compared with other groups. ERα mRNA levels significantly increased during labor compared with days 15-21 of pregnancy. Compared with control animals, ERα mRNA levels decreased significantly in OVX virgin rats implanted with tubes containing progesterone for one week; 24 h following the removal of the progesterone tubes, ERα mRNA levels were found to be similar to control levels. Estrogen treatment following OVX on day 18 of pregnancy caused increased OTR mRNA levels, whereas ovariectomy alone increased ERβ mRNA but not ERα mRNA. Results from the present study suggest that ERα and ERβ mRNA expressions are differentially regulated in the rat uterus. Moreover, during spontaneous labor our findings appear to suggest that ERα plays a more prominent role than ERβ in mediating estrogen action in the induction of uterine OTR mRNA before labor.
We studied the kinetics of iodine in various forms, in order to establish appropriate guidelines of iodine prophylaxis for thyroid blockade at nuclear emergency in "iodine rich areas", such as Japan. First, the effect of equivalent dose of potassium iodide (KI) (solution vs. tablet) was evaluated with excretions of urinary iodine (UI) at Nagasaki, Japan, and it was revealed that there was no difference of iodine kinetics between solution and tablet. We also performed the same study at Gomel, Belarus, which was known to be an iodine deficient area, and obtained the same results. Second, the kinetics of iodine included in "iodine rich" food was also evaluated with excretions of UI. Interestingly, the ratio of UI excretion with iodine rich food was significantly lower than that with KI tablets until 6 h after the intake (ANOVA, p = 0.02). These results proved that 1) KI solution as well as its tablet is useful for prophylaxis and 2) prophylaxis by iodine rich food is not effective for rapid blockade of thyroid gland at nuclear emergency. Finally, we emphasized that the approach from social medicine is definitely important to establish an effective iodine prophylaxis.
TSH receptor antibodies (TRAb) are generally regarded as mediators of thyroid stimulation in Graves' disease. In addition, a high serum TRAb value during pregnancy is one of the risk factors for intrauterine death, prematurity, and fetal or neonatal hyperthyroidism. Recently, correlations between a high serum TRAb value and endocrine opthalmopathy were also suggested. Surgical resection of the thyroid is usually followed by a reduction of serum TRAb levels in variable degrees. The relation between the extent of the thyroidectomy and the degree of reduction is still controversial. In addition, the changes in the TRAb value after total thyroidectomy (TT) over a long period of time have never been studied. We studied the changes in serum TRAb values after TT and subtotal thyroidectomy (ST) for more than 7 years. Forty-one patients with Graves' disease underwent TT, and 99 patients underwent ST. The serum TRAb values and the ratio of the patients who achieved normal values among each group (normalization rates of TRAb) at 3 and 6 months, 1, 3, 5 and 7 years after surgery were compared between the TT group and ST group. The mean preoperative TRAb values were not significantly different between the TT and ST groups, and the mean TRAb values measured 3, 6 and 12 months after surgery were not significantly different between the groups. However, the TRAb values measured 3, 5 and 7 years after surgery were significantly (p<0.05) lower in the TT group than in the ST group (16.7 ± 3.3% vs 28.0 ± 2.6%, 12.6 ± 3.4% vs 29.3 ± 3.8%, 5.6 ± 0.9% vs 25.4 ± 4.1%, respectively). The normalization rates of TRAb were not significantly different between the groups until 1 year after surgery. However, the normalization rates 3, 5 and 7 years after surgery were significantly (p<0.05) higher in the TT group than in the ST group (65.7% vs 42.4%, 77.3% vs 46.7%, 100% vs 59.1%, respectively). The surgical complication rates of TT were similar to ST except for permanent hypoparathyroidism. TT is a treatment option for Graves' disease, especially in patients with a high TRAb value who wish to have children or who have Graves' opthalmopathy.
We investigated the effect of highly purified eicosapentaenoic acid ethyl ester (EPA-E) on blood coagulation abnormalities and dysfunction of vascular endothelial cells in spontaneously diabetic Otsuka Long-Evans Tokushima Fatty rats. The animals were treated with either EPA-E or lard at a daily dose of 0.3 g/kg/day for 52 weeks by gavage, and their coagulation/fibrinolytic parameters, platelet aggregation, and functions of the vascular endothelial cells were examined. EPA-E significantly improved coagulation-related parameters including prothrombin time, activated partial thromboplastin time, fibrinogen level, and activities of factor II, V, VII, VIII, IX, X, XI, and XII, and antithrombin III, and fibrinolysis-related parameters including plasminogen, tissue-type plasminogen activator, α2-plasmin inhibitor, and plasminogen activator inhibitor. It also suppressed ADP- or collagen-induced platelet aggregation and the cholesterol/phospholipid molar ratio in platelet membranes at a dose of 0.3 g/kg. In addition, it significantly increased the migration activity of vascular endothelial cells, and decreased the binding of vascular endothelial cells to vascular endothelial growth factor. In contrast, lard had no effect on hypercoagulation, hypofibrinolysis, and platelet hyperaggregation but significantly aggravated the dysfunction of vascular endothelial cells. These data demonstrate that EPA-E beneficially altered certain factors known to promote thrombosis and atherosclerosis in this animal model.
Objective of the present study is to determine the estrogenic effect of isoflavone on vaginal epithelia and bone metabolism in early postmenopausal women. Twenty-two postmenopausal women were randomly assigned to either a group that was given isoflavone extract (61.8 mg) for three months or a control group that was given placebo. We measured the L2-4 bone mineral density (BMD) before and 3 months after treatment by dual X-ray absorptiometry (DXA). Blood and urine samples were obtained from the women before and 3 months after treatment. We measured FSH using radioimmunoassay and, urinary pyridinoline and deoxypyridinoline levels by HPLC. For endocrine cytology, vaginal smears were collected before and 3 months after the treatment. Three months after the treatment, the serum FSH levels and the BMD values did not significantly differ between the two groups. Urinary excretion of isoflavone was significantly higher in the group given isoflavone compared with that given placebo (p<0.03). Numbers of parabasal and intermediate types of cells were significantly decreased (58.2 ± 12.4% to 25.0 ± 10.7%; p<0.05) and increased (24.1 ± 8.7% to 63.7 ± 10.7%; p<0.05), respectively in the isoflavone group, but remained unchanged in the control group. Urinary pyridinoline excretion was significantly decreased (49.6% vs. before, p<0.01 by paired t-test) in the isoflavone group. The intake of 60 mg of isoflavone daily for 3 months produced maturational changes of vaginal epithelia without affecting serum FSH levels, and could possibly slow down bone turnover rates as judged by decreased urinary pyridinoline excretion.
Ionising radiation is used for the treatment of pituitary tumours as fractionated radiotherapy, where the total dose reaching the tumour area is in the range of 40–50 Gy, or during stereotactic radiosurgery, where the total dose reaching the tumour area during one session is in the range of 20–90 Gy. In this study, we investigated the effect of ionising radiation of 60Co (dose rate of 3 Gy/min, similar to that used during gamma knife procedure) on the mode of cell death of the somatomammotroph pituitary cell line, GH3, an immortalized cell line derived from a rat pituitary adenoma. We found that the basic mechanism of cell death induced by irradiation of this GH3 cell line by γ-rays was programmed cell death—apoptosis. Doses of 20–50 Gy were shown to inhibit proliferation in these cells. 24 hours after irradiation with a dose of 20 and 50 Gy, cells were shown to accumulate in the G2/M phase of cell cycle. This cell cycle arrest lasted for at least ten days. Apoptosis was detected 72 hours towards until the end of the study (10 days). However, a significant number of cells were still alive ten days following irradiation. We conclude that ionising radiation doses of 20 and 50 Gy induce pituitary GH3 cell apoptosis following cell cycle arrest in the G2/M phase.
To evaluate the clinical usefulness of serum soluble Fas (sFas) and sFas ligand as a prognostic factor and for monitoring the regression and progression of metastatic prostate cancer treated with endocrine therapy, sFas and sFas ligand were measured in sera collected from 30 patients with untreated metastatic prostate cancer. sFas levels were measured sequentially in 16 patients who had progressed to a state of elevated prostate-specific antigen (PSA) and 5 patients who were in regression following endocrine therapy. Serum sFas levels in patients with metastatic prostate cancer were found to be significantly higher than that of control patients with benign prostate hyperplasia. Patients with low levels of serum sFas had a higher cause-specific survival rate and a higher PSA progression-free rate compared with patients with high levels of serum sFas. In patients who suffered PSA progression following endocrine therapy, serum sFas increased in parallel to the increase in PSA levels although the magnitude of change in sFas was very small. In patients whose tumor regressed following therapy, sFas levels did not change. sFas ligand levels were very low or below measurable levels in all specimens. sFas levels might be associated with poor prognosis in metastatic prostate cancer. Serum sFas ligand appears to have limited clinical relevance.
Transsphenoidal surgery is the first therapeutic option in acromegaly, but the management of persistent or recurrent cases of the disease after surgery has been controversial. This study presented the results of secondary transnasal surgery for residual or recurring growth hormone (GH)-secreting macroadenoma with reference to intraoperative GH measurement. It focused on 22 patients who underwent secondary transsphenoidal surgery for 18 residual and 4 recurring GH-secreting pituitary macroadenomas from 1990 to 1999. To assess complete tumor removal, plasma GH concentration was measured intraoperatively. Before secondary surgery, plasma GH levels without medical treatment ranged from 2.0 to 239.0 μg/l (mean 31.5 +/– 50.4). Magnetic resonance imaging demonstrated 16 transnasally resectable tumors and 6 nonresectable grossly invasive tumors. Intraoperative plasma GH concentrations declined sufficiently in 9 of 16 with transnasally resectable tumors, but in the remaining 7 cases the tumors were further explored and normalization of GH levels was ultimately obtained in 4 out of these cases. It was impossible to completely remove the tumors in all the 6 patients with transnasally nonresectable tumors. Thirteen of 22 patients achieved endocrinological remission by rigorous criteria. In transnasally resectable tumors, the endocrinological remission rate was 81.3% (13 of 16 patients) with no recurrence during the follow-up period of at least 4 years. Secondary transnasal surgery for residual or recurring GH-secreting pituitary macroadenomas is a safe and effective treatment, if done along with intraoperative GH measurement. Endocrinological remission can be obtained with high probability in patients who suffer from macroadenomas with suprasellar extension, with the exception of transnasally nonresectable grossly invasive tumors.
Glucose-dependent insulinotropic polypeptide (GIP), a peptide released from the intestines after meals, is thought to stimulate insulin secretion. GIP receptor cDNA has recently been cloned and its mRNA has been recognized in several organs including the pituitary, but the physiological roles of GIP receptors of the pituitary have yet to be determined. We have demonstrated the possibility that GIP stimulates GH secretions from the pituitary adenoma cells of acromegalics. GIP-stimulated GH responses were studied in four acromegalics. In two acromegalics whose GH showed paradoxical secretion to oral glucose tolerance test (OGTT), GIP infusion (0.6 μg/kg/h) drove GH secretion (13.7 to 68.1, 22.5 to 76.2 ng/ml, respectively). However, in the other two acromegalics whose GH showed no paradoxical response to OGTT, GIP infusion did not induce GH secretion. One of the patients who was studied extensively had a GH that responded to OGTT. This patient's serum GH levels increased after meals while adenomectomy abolished both the paradoxical GH secretions by OGTT and GH responses to the GIP infusion. These data suggested that some somatotroph adenoma cells have an aberrant response to GIP which may go toward explaining paradoxical GH secretions to OGTT in acromegalics.