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Recent molecular and biochemical analyses have revealed the presence of corticotropin-releasing factor (CRF) and urocortin (Ucn), together with their corresponding receptors in mammalian skin. The melanosomal enzyme tyrosinase-related protein 1 (TRP1) is involved in modulation of pigment production in response to stressors. Although CRF and Ucn are thought to have potent effects on the skin system, their possible roles and regulation have yet to be fully determined. This study aimed to explore the effects of CRF and Ucn on TRP1 gene expression using human melanoma HMV-II cells. The mRNA of CRF, Ucn1, Ucn2, and CRF receptor type 1 (CRF1 receptor) was detected in HMV-II cells. CRF and Ucn1 stimulated TRP1 gene transcription via the CRF1 receptor, and increased both Nurr-1 and Nur77 mRNA expression levels. Both CRF- and Ucn1-induced Nurr-1/Nur77 acted via a NGFI-B response element on the TRP1 promoter. The combination of Nurr-1/Nur77 and microphthalmia-associated transcription factor, a melanocyte-specific transcription factor gene induced by α-melanocyte-stimulating hormone, had additive effects on activation of TRP1 gene transcription. The findings suggest that in human melanoma HMV-II cells both CRF and Ucn1 regulate TRP1 gene expression via Nurr-1/Nur77 production, independent of pro-opiomelanocortin or α-melanocyte-stimulating hormone stimulation.

Corticotropin-releasing factor (CRF) and arginine vasopressin (AVP) play a central role in regulating the stress response. In response to stress, CRF and AVP neurons in the hypothalamic paraventricular nucleus secrete the peptides to stimulate the release of adrenocorticotropic hormone from the anterior pituitary. Ghrelin, an endogenous ligand of the growth hormone-releasing peptide receptors (GHSR), has been shown to stimulate the release of CRF and AVP by rat hypothalamic explants. However, little is known about the ability of the ghrelin signaling pathways to activate the CRF and AVP genes in the hypothalamus. In the present study, we examined the direct effect of ghrelin on CRF and AVP gene expression in hypothalamic 4B cells, which show the characteristics of the hypothalamic parvocellular paraventricular nucleus neurons. Cells were transfected with CRF or AVP promoter to examine the activity of each promoter. Ghrelin stimulated the promoter activities and mRNA levels for both CRF and AVP. The involvement of a protein kinase pathway was examined using inhibitors. Protein kinase A and phospholipase C pathways were shown to be involved in ghrelin-induced increases in both CRF and AVP promoter activities. GHSR type 1a (GHSR1a) mRNA levels were also increased by ghrelin, and these ghrelin-induced levels were suppressed by a GHSR1a antagonist. Thus, ghrelin-dependent pathways are involved in the regulation of CRF and AVP gene expression in the hypothalamus: ghrelin, an orexigenic hormone, stimulates CRF, an anorexigenic/anxiogenic factor in the hypothalamus, resulting in hypothalamic-pituitary-adrenal axis activation to stimulate the release of glucocorticoids.

In June, 2009, a 51-year-old woman presented with a 4-day history of abdominal swelling and fever, and a 2-week history of loss of appetite. There was no history of abdominal pain or nausea. She was febrile (38·4°C) and her abdomen was swollen but soft without spontaneous pain or tenderness. She had a history of schizophrenia since the age of 40 years which was well controlled with perospirone 12 mg/day and quetiapine 150 mg/day. At the age of 45 years, she was diagnosed with diabetes mellitus and had achieved good glycaemic control (HbA1c 6·5%) with biphasic insulin aspart 30 (6 U/day). There was no sign of obvious peripheral neuropathy. Laboratory test results showed normocytic anaemia (haemoglobin 95 g/L), leucocytosis (13·3×109/L) with neutrophilia (91·5%), high concentration of C-reactive protein (129 mg/L), and normal liver and kidney function. Urinalysis showed negative protein and no leucocytosis. Chest radiography showed normal lungs with no cardiac enlargement. Abdominal CT showed a large volume of partly encapsulated ascites (fi gure). The peritoneum in her pelvic cavity was thickened, and ascites in the right inferior abdominal cavity contained calcifi cation and air (fi gure). The aspirated ascitic fl uid had an unpleasant smell and was suppurated. Culture of the fl uid was positive for pyogenic agents, including Peptostreptococcus spp and Bacillus subtilis. Blood culture was negative. We diagnosed severe bacterial pan-peritonitis. Surprisingly, her general condition was stable and she did not complain of any abdominal pain. Abdominal drainage was done and antibiotics started (imipenem/ cilastatin 1·5 g/day), but her symptoms did not improve. Therefore, laparotomy was done on the seventh day of admission. On laparotomy, a large amount of yellowish, turbid, gel-like material fi lled the abdominal cavity with retention of pus in the pouch of Douglas. The appendix was necrotic and contained faecolith. The bacterial peritonitis was suspected to be caused by perforation associated with acute appendicitis. Postoperative course was uneventful, and the patient recovered. When last seen in October, 2009, the patient was well. Even though our patient had a purulent pan-peritonitis caused by a perforated appendix, she did not present with abdominal pain, tenderness, or guarding. Diminished pain sensitivity or loss of pain sensation in people with schizophrenia has previously been reported in cases of acute myocardial infarction and perforated gastrointestinal tract. Clinically, diminished pain sensitivity in schizophrenia has been linked to key features of the disorder, such as positive symptoms, aff ective fl attening, or attention defi cits. Disturbances in dopamine, serotonin, glutamate, and opioids have been proposed to account for hypoalgesia in schizophrenia. Hypoalgesia in schizophrenia has been reported throughout the acute phase of illnesses and in medicated stable or drug-free patients; neuroleptic drugs have been suggested to have minor analgesic eff ects. Diabetes occurs in people with schizophrenia two to four times more often than in the general population. Compared with people without diabetes, appendicitis in people with diabetes is more likely to result in perforation or other complications. Decreased pain sensation may result in aggravation of the condition and in a delay of diagnosis and treatment. Our case is an important reminder that people with schizophrenia do not always present with typical clinical features of acute abdominal disease pathology.

Introduction: Corticotropin-releasing factor (CRF) plays a central role in controlling the hypothalamic-pituitary-adrenal (HPA) axis during stressful periods. CRF is synthesized and secreted in the hypothalamic paraventricular nucleus (PVN) in response to stress, and stimulates ACTH in the pituitary corticotrophs. ACTH stimulates the release of glucocorticoids from the adrenal glands, and glucocorticoids sequentially inhibit hypothalamic PVN production of CRF and pituitary production of ACTH. The effects of glucocorticoids on CRF gene regulation, however, are possibly tissue-specific since glucocorticoids stimulate CRF gene expression in the placenta and the bed nucleus of the stria terminalis, while they inhibit it in the hypothalamus. Methods and results: In a hypothalamic cell line, 4B, we found that forskolin-stimulated CRF gene transcription was mediated by a functional cAMP-response element (CRE), which included −220 to −233 bp on the CRF 5′-promoter region. Protein kinase A, protein kinase C, and p38 mitogen-activated protein kinase pathways contributed to forskolin-induced transcriptional activity of CRF in hypothalamic 4B cells. Glucocorticoid-dependent repression of cAMP-stimulated transcriptional activity of CRF was localized to promoter sequences between −278 and −233 bp, which included a glucocorticoid regulatory element and a serum response element. Conclusion: Taken together, these findings indicate that the regulatory elements, including CRE, negative glucocorticoid regulatory element, and a serum response element on the promoter, contribute to the regulation of CRF gene transcription in hypothalamic 4B cells.

Adrenal insufficiency can result from primary disorder of the adrenal gland or occurs secondarily due to deficiency in adrenocorticotropic hormone (ACTH) or corticotropin-releasing hormone (CRH). To prevent adrenal crisis, it is thus important to test the remaining function of the adrenal gland. Tests for the function of the hypothalamic-pituitary-adrenal (HPA) axis are also useful for examining localization of disease causing adrenal insufficiency. Generally, the insulin tolerance test (ITT) is useful for examining the HPA axis in both hypothalamic and pituitary diseases; however, ITT has a number of disadvantages. The growth hormone-releasing peptide (GHRP)-2 test may be a useful tool for diagnosing secondary adrenal insufficiency such as hypothalamic disorder and pituitary damage. In the present study, we examined the diagnostic usefulness of the GHRP-2 test as a substitute for ITT in hypopituitarism. We showed that patients with significant ACTH response to ITT also had significant response to the GHRP-2 test, while patients with no significant ACTH response to ITT also had no significant response to the GHRP-2 test. These data suggest that the GHRP-2 test may be a useful diagnostic tool for secondary adrenal insufficiency such as hypothalamic disorder and pituitary damage.

We present a unique case of an adenoma secreting growth hormone (GH), showing incomplete nerve bundle formation without ganglion cells. A 47-year-old man presenting with acromegaly was revealed to have high serum GH and IGF-1 levels. The concentrations of the other adenohypophysial hormones were within the normal range. Histology revealed an unusual pituitary adenoma containing many nerve bundle-like structures. Adenoma cells with ovoid or round hyperchromatic nuclei and eosinophilic cytoplasms lacked the typical features of ganglion cells. The nerve bundles consisted of slender elongated cells. These fibers were arranged into groups in a roughly parallel fashion. By immunohistochemistry, many adenoma cells were positive for GH, prolactin, thyrotropin beta, synaptophysin and chromogranin. Fibrous bodies revealed by keratin immunostaining were found only in adenoma cells. Scattered star-shaped adenoma cells showed the same immunoreactivity as folliculo-satellite cells. Adenoma cells, but not the bundle-like structures, were also positive for Pit-1. Immunostaining for neurofilament protein, GFAP, vimentin, and S-100 protein revealed variable amounts of fibrils within the bundle-like structures. Scattered immunoreactivity for myelin basic protein and synaptophysin was also found in the bundle area. Our case is the first GH-secreting pituitary adenoma showing incomplete nerve bundle differentiation and lacking mature ganglion cells.

Acromegaly is caused primarily by pituitary growth hormone (GH)-secreting tumors. It is usually recognized because of characteristic manifestations, and diagnosed clinically. However, there exists a mild stage of acromegaly, which poses a diagnostic problem due to the absence of typical clinical manifestations. Here we present four patients with pre-clinical acromegaly, who showed minimal acromegaloid features with elevated levels of insulin-like growth factor-I. Basal GH levels were within normal levels in 3 of 4 cases, while insulin-like growth factor-I levels were elevated above normal in all cases. Plasma GH levels were elevated in response to thyrotropin-releasing hormone (TRH) in all cases, indicating a diagnostic value of the TRH stimulation test. In contrast, an oral glucose tolerance test was not useful for the diagnosis, because of the low GH levels (less than 1 ng/ml) and/or secondary to diabetes mellitus. In response to a dopamine agonist, GH levels were increased in the two cases, whereas GH levels were decreased or remained unchanged in the other two cases. We therefore suggest that the TRH stimulation test would be helpful to examine the presence of pre-clinical acromegaly. Diagnosis of the early stages of acromegaly is important to prevent progression to overt acromegaly.

The glucose-induced insulin secretion is fine-tuned by numerous factors. To systematically identify insulinotropic factors, we optimized a primary β-cell-based functional assay to monitor intracellular Ca2+ flux ([Ca2+]i). By this assay system, we successfully identified several insulinotropic peptides including cholecystokinin, gastrin releasing peptide, vasopressin, and oxytocin from tissue extracts. Screening of an assortment of chemical compounds, we determined three novel insulin secretagogues: N-arachidonylglycine (NAGly), 3β-(2-diethylamino-ethoxy) androstenone hydrochloride (U18666A), and 4-androstene-3,17-dione. The NAGly increased [Ca2+]i through stimulation of the voltage-dependent Ca2+ channels and it was dependent on extracellular glucose level. On the other hand, U18666A and 4-androstene-3,17-dione increased [Ca2+]i in the presence of KATP channel opener diazoxide while it was inhibited by the presence of Ca2+ channel blocker nitrendipine, suggesting that their effects are independent of KATP channel. These unique features will be useful for further development of insulinotropic factors and drugs for treating type 2 diabetes.

Glycyrrhizic acid (GA) inhibits the activity of 11beta-hydroxysteroid dehydrogenase type 2 in the kidney, with the resulting increase in intrarenal cortisol concentration leading to hypertension and suppression of the renin-aldosterone system. In this paper we describe an interesting case of pseudoaldosteronism, associated with hypocalcemia and an exaggerated ACTH response. A 72-year-old woman was referred to our department for further evaluation of hypokalemia and hypocalcemia. The patient had been taking GA (150 mg/day) for the previous year for treatment of liver damage. Plasma renin activity and aldosterone concentration were both within lower normal limits. Urinary excretion of potassium and calcium was within the upper limit of the normal range and increased with administration of supplements. Plasma ACTH levels increased markedly in response to an intravenous injection of CRH. Cessation of GA and the potassium and calcium supplements on admission, led to a gradual normalization of serum potassium and calcium levels and blood pressure. The hypocalcaemia in our patient was related to decreased tubular reabsorption of calcium as a consequence of renal corticoid excess. It is possible that an increase in the number of CRH receptors in the pituitary following GA treatment caused the exaggerated ACTH response in association with pseudoaldosteronism. The existence of hypocalcemia and an exaggerated ACTH response should be observed carefully when managing pseudoaldosteronism.

Mutations in genes encoding transcription factors that control pituitary development cause early-onset pituitary hormone deficiencies. Now, circulating antibodies against one such factor, PIT1, have been identified as being responsible for hormone deficits and pituitary cell loss similar to those caused by mutations of its gene POU1F1 but with a late onset.

A 48-yr-old woman was referred to our hospital for evaluation of a left adrenal mass. An abdominal computed tomography scan demonstrated a 5.4 3.7-cm tumor in the left adrenal gland (Fig. 1, A and B). She had untreated hypertension on admission and no Cushingoid features. When in a seated position, the patient’s urinary aldosterone excretion rate was 19.4 g/d, plasma aldosterone concentration (PAC) was 20.8 ng/dl, and plasma renin activity (PRA) was 0.8 ng/ml h mid morning. Her plasma aldosterone to renin ratio was 26.0. She was diagnosed with normokalemic (serum potassium, 3.8 mmol/ liter) primary aldosteronism after captopril challenge (PAC, 15.2 ng/dl; PRA, 0.4 ng/ml h at 2 h) and furosemide-plus-upright tests (PAC, 65.4 ng/dl; PRA, 0.3 ng/ ml h at 2 h) (1). 18F-Fluorodeoxyglucose (FDG) positron emission tomography demonstrated a marked uptake of FDG in the left adrenal mass (Fig. 1, C and D). The mass was therefore clinically diagnosed as an aldosterone-producing adrenocortical carcinoma (2). After left adrenalectomy, the patient’s hypertension improved with normalizationofaldosterone to renin ratio.Lightmicroscopic examination revealed the cells within the main tumor body to have abundant eosinophilic cytoplasm and three positive scores in Weiss criteria, namely, nuclear atypia, architecture, and an eosinophilic cytoplasm (Fig. 2A). The eosinophilic tumor cells were positive for steroidogenic factor-1, but negative for steroidogenic enzymes [3 -hydroxysteroid dehydrogenase (3BHSD), P450c21, P450c17, and dehydroepiandrosterone sulfotransferase]. This main tumor body was therefore diagnosed as a true nonfunctioning adrenocortical tumor, an “oncocytoma” (3). A wellcircumscribed localized mass of clear cortical cells demonstrating marked P450 side-chain cleavage enzyme, 3BHSD and P450c21, and weak P450c17 immunoreactivity was detected around one margin of the oncocytoma (Fig. 2, B–E).Theattachedzonaglomerulosawashyperplasticbut negative for 3BHSD, evidence pointing toward a nonfunctioning albeit hyperplastic response in the neighboring normal glomerulosa. This part was therefore histopathologically diagnosed as an aldosteronoma. Although it could be one tumor with heterogeneity, this is the first