Postpartum thyroid dysfunction is rather a common problem during postpartum period, found in approximately 5% of mothers in the general population. It occurs from subclinical autoimmune thyroiditis that is aggravated after parturition and causes various types of thyroid dysfunction. Immune activity is physiologically suppressed during pregnancy so that the fetus is not rejected, and rebounds above the normal level after parturition. Graves' disease and Hashimoto's thyroiditis spontaneously ameliorate during pregnancy, and are often aggravated after parturition. The high-risk mothers for postpartum thyroid dysfunction can be well screened by anti-thyroid microsomal antibody (MCAb) and 60% to 70% of MCAb-positive mothers develop postpartum thyroid dysfunction, which is transient in most cases. New onset of Graves' disease may be screened by thyroid stimulating antibody (TSAb) and 70% of TSAb-positive mothers develop either transient or persistent postpartum Graves' disease that usually occurs at 3-6 months postpartum. Immune rebound after parturition may not cause only autoimmune thyroid diseases but other autoimmune Table 4. Various types of postpartum autoimmune disease diseases, which may be investigated with the similar strategies to those in postpartum autoimmune thyroid disease. Thus, we found that postpartum onset of rheumatoid arthritis occured in 0.08% of women in the general population and could be partially predicted by measuring rheumatoid factors in early pregnancy. There are several case reports of other autoimmune diseases developed after delivery; postpartum renal failure or post-delivery hemolyticuremic syndrome, postpartum idiopathic polymyositls, postpartum syndrome with antiphospholipid antibodies, postpartum autoimmune myocarditis. Many other possible postpartum autoimmune diseases are still unexplored. Postpartum autoimmune thyroid syndrome is a good model for understanding the mechanism of onset and aggravation of other autoimmune diseases. Prediction and prevention of postpartum onset of many autoimmune diseases could be established in the near future.

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The goal of this study was to improve assessment of diagnostic measures for lateral localization of aldosterone-producing adrenal adenomas preparatory to retroperitoneoscopic removal, in view of the fact that this technique allows for only unilateral access. A retrospective study was carried out of the medical records of 64 patients (38 women, 26 men, average age 46.8±11.2) who underwent surgery at University Hospital, Münster, between 1969 and 1998. Seventeen of the 64 patients presented with hyperplasia and 47 had adrenal adenoma. In cases of hyperplasia, computerized tomography imaged a false-positive unilateral tumor 10 times, a false-negative 3 times, and a unilateral hyperplasia 1 time (ultrasonography: tumor 2 times, false-negative 3 times; ¹³¹I-Iodomethylnorcholesterol scintigraphy: tumor 5 times, false-negative 1 time, correct 1 time). In cases of adenoma, computerized tomography yielded accurate results 40 times, imaged a false-negative 2 times, and indicated the incorrect side 1 time (Ultrasonography: false-negative 12 times, correct side 9 times, incorrect side 1 time; ¹³¹I-Iodomethylnorcholesterol scintigraphy: correct side 19 times, false-positive (both sides) 5 times, negative 3 times, incorrect side 2 times). Venous sampling, which was carried out seven times, yielded accurate results six times, and failed technically one time. Venous sampling appears to be the method of choice for preoperative lateral localization. Thus, retroperitoneoscopic treatment of Conn's syndrome should not be carried out unless venous sampling is carried out first.

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A case of isolated ACTH deficiency who developed autoimmune-mediated hypothyroidism and still showed impaired water diuresis during glucocorticoid replacement therapy is reported. A 45-year-old woman was initially admitted for nausea, vomiting, and general malaise. Her serum sodium and plasma osmolality, ACTH and cortisol values were low, but her urine osmolality was high. Other pituitary hormone levels, thyroid hormone levels, and a computed tomogram of the pituitary gland were normal. The patient was treated with hydrocortisone and followed in the outpatient clinic; however, she was lost to follow up 18 months after admission. Three years later she presented with hypoglycemia and hyponatremia. Her serum or plasma ACTH, FT3, FT4, cortisol levels were low and her serum TSH level was high. Pituitary stimulation tests revealed a blunted response of ACTH to CRH and an exaggerated response of TSH to TRH. Plasma ADH was inappropriately high, and a water-loading test revealed impaired water diuresis and poor suppression of ADH. Although ADH was suppressed, impaired water diuresis was observed in the water loading test after hydrocortisone supplementation. Thyroxine supplementation completely normalized the water diuresis. Her outpatient clinic medical records revealed a gradual increase in TSH levels during follow up, indicating that she had developed hypothyroidism during glucocorticoid replacement therapy. The hyponatremia on the first admission was due to glucocorticoid deficiency, whereas the hyponatremia on the second admission was due to combined deficiencies of glucocorticoid and thyroid hormones.

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We examined the effects of PTH, calcitonin (CT) and parotin subunit on the intracellular Ca ²⁺ of odontoblasts using a chelate reagent, FURA2-AM. Rat CT (rCT), at a final concentration of 0.01μM, induced a gradual lowering of Ca²⁺, and addition of ATP, in the presence of CT, resulted in a partial and short-lasting recovery of Ca²⁺. At higher concentrations, it caused a rapid decrease of Ca²⁺. CTs of other animal species showed similar effects. Human PTH (hPTH) added at concentrations of 0.01, 0.1 and 1μM, caused no significant changes in intracellular Ca²⁺. Parotin subunit caused a rapid lowering of Ca²⁺ which was seen already at 0.01μM. rCT added after treatment with hPTH caused an immediate decrease of Ca²⁺ to zero level, showing that CT action was enhanced by pretreatment with hPTH. This enhancement was also confirmed by addition of hPTH after rCT, where at 1μM, it caused further acute decrease in Ca²⁺. After intracellular Ca ²⁺ was lowered by CT pretreatment, parotin, at 0.1μM, induced a further but gradual decrease of Ca²⁺. The present results, together with our previous study indicating that hPTH increased cAMP production and that CT inhibited the PTH action, made it clear that all the hormones affect odontoblasts, and that CT and parotin act via Ca-related signal transduction system, while PTH acts via CAMP-PKA-related cascade. Possible crosstalk of both systems was also suggested.

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Denys-Drash syndrome (DDS) is characterized by genital anomaly, early onset nephropathy and high risk for developing Wilms' tumor (WT). Recently, mutations in exon 8 or 9 of the Wilms' tumor suppressor gene (WT1) have been found in the majority of DDS patients studied. We analyzed these two exons of the WT1 gene in genomic DNA from two female patients with DDS by using polymerase-chain reaction (PCR) and direct sequencing. The patients were accompanied with normal external genitalia, early onset renal failure between 6 and 12 months of age, and unilateral Wilms' tumor. Genomic DNA was isolated from peripheral blood leucocytes of the patients. Amplification of exons 8 and 9 of the WT1 gene by PCR was performed, and direct sequencing of the PCR product was performed using an automatic DNA sequencer. Two heterozygous missense mutations were found in these patients, including a missense mutation in exon 9 at codon 388 replacing the wild-type Cys with Phe, and a previously described mutation in exon 9 at codon 398 replacing the wild-type Leu with Pro. Cys388Phe is a novel mutation in the WT1 gene in the DDS. These cases are considered to be “incomplete DDS” with nephropathy and Wilms' tumor and without genital anomaly, the validity of which has been confirmed by mutation analysis.

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We had the opportunity to closely observe a unique case of central diabetes insipidus (DI), in which dramatic changes in both radiological findings and hypophysial functions were seen. A 63-year-old female developed central DI, and magnetic resonance imaging (MRI) revealed a mild thickening of the pituitary stalk and lack of hyperintense signal associated with normal neurohypophysis on T1-weighted images. About three months later, the stalk was found to be remarkably expanded like neoplasm; however, anterior pituitary functions were almost normal on that occasion, except for the absence of GH response to an insulin tolerance test. About nine months after the onset of DI, secondary hypoadrenalism and hypothyroidism, which required replacement therapy, developed transiently, but recovered about one year later. Results of hypophysial endocrine tests during this period showed that the dysfunction was predominantly suprapituitary in nature. As time passed, the stalk lesion began to shrink spontaneously and another MRI, obtained five years after the onset of DI, disclosed normal findings for the infundibulo-hypophysial system, except for lack of the hyperintense signal of the neurohypophysis. The patient has since been healthy, except for the DI, which has been controlled by treatment with vasopressin. We report here a unique case of central DI associated with transient pituitary stalk enlargement.

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The liver plays important roles in the clearance and metabolism of sex steroids. Its dysfunction is considered to influence the metabolic pathways of sex steroids, and to result in gynecomastia and other abnormalities of sex steroids. However, the details of its mechanism have not been well-characterized. We therefore examined the enzymes involved in the hepatic clearance and/or metabolism of sex steroids in human liver and its disorders using immunohistochemistry to determine whether there are any abnormalities of expression of these enzymes in human liver disorders. These enzymes are 17β-hydroxysteroid dehydrogenase (17β-HSD) type 2, an enzyme that catalyzes the biologically active estrogen, estradiol (E2), to inactive estrogen, estrone (E1), and dehydroepiandrosterone sulfotransferase (DHEA-ST), which catalyzes sulfonation of dehydroepiandrosterone (DHEA) to form biologically inactive DHEA-S. A total of 162 cases including normal liver (n=31), chronic hepatitis (n=41), liver cirrhosis (n=21), hepatocellular carcinoma (n=47), cholangiocellular carcinoma (n=22) and fetal liver (n=4) were examined by immunohistochemistry. Both enzymes were expressed in the hepatocytes around portal area and central vein in normal liver. Immunopositive area for DHEA-ST was significantly larger in chronic hepatitis than in normal liver, but that of 17β-HSD type 2 in chronic hepatitis was not different from normal liver. There were no significant differences in the immunopositive area for both enzymes between liver cirrhosis and normal liver. In hepatocellular carcinoma, immunoreactivity for both enzymes were categorized into Group A, or low positive group, and Group B, or high positive group. The latter tended to be poorly differentiated carcinoma. In cholangiocellular carcinoma, immunopositive areas of both enzymes were significantly smaller than those of normal liver. These findings indicate that the amount of expression of the enzymes involved in metabolism and/or clearance of sex steroids per hepatocyte did not decrease in liver cirrhosis. Therefore, sex steroids' abnormalities may be due to the decreased quantity of hepatocytes associated with liver cirrhosis. In hepatocellular carcinoma, some poorly differentiated cases were associated with increased expression of 17β-HSD type 2 but its biological significance needs to be determined by further studies.

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Profiles of circulating plasma inhibin A and inhibin B during sexual maturation in male chimpanzees were investigated by using two-site enzyme-linked immunoassay (ELISA). Plasma concentrations of testosterone and pituitary gonadotropins were also measured. Concentrations of inhibin B, testosterone, luteinizing hormone (LH) and prolactin increased with age throughout prepuberty to adulthood, whereas inhibin A level was low and there were no age-related changes in concentrations of either inhibin A and follicle-stimulating hormone (FSH). Inhibin B showed an inverse correlation with FSH in adult (7 years or order) but not in immature (6 years or younger) male chimpanzees. There was no correlation between plasma levels of FSH and testosterone throughout the period of sexual maturation. However, testosterone levels were positively correlated with inhibin B levels. These results suggest that circulating inhibin B is involved in the regulation of FSH secretion after puberty in adult male chimpanzees, and also that circulating inhibin B is an important form of inhibin as a marker of Sertoli cell function in adult male chimpanzees.

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Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) is a genetic disorder characterized by unregulated insulin secretion and profound hypoglycemia. Recently, mutations of SUR1 and Kir6.2, which constitute the pancreatic β-cell ATP-sensitive potassium (K_ATP) channel, have been shown to be associated with familial PHHI in certain ethnic groups. In the present study, we examined clinical symptoms, therapy, and variations in the SUR1 and Kir6.2 genes in eight Japanese patients with PHHI. Four patients were being treated with pharmacological agents and the other four had required pancreatectomy to normalize glucose levels. There was no difference in timing of the onset of hypoglycemia between the groups. There also was no difference in severity between the two groups, as assessed by blood glucose levels, plasma insulin levels, and birth weight. However, all of the pancreatectomized patients and none of the medically treated group had presented with seizures. By genetic screening, we found eleven nucleotide substitutions in the SUR1 gene, three of which result in amino acid changes, and three nucleotide substitutions in the Kir6.2 gene, two of which result in amino acid changes, but all of these genetic variants had been previously reported in normal subjects. These results indicate that the mechanism of hypoglycemia in these patients is different from those previously reported in PHHI patients, giving further support to the view that PHHI is a heterogeneous disorder.

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We examined clinical, endocrinological and molecular biological aspects of an estrogen-secreting adrenal carcinoma in an 18-month-old male to clarify the pathogenesis of this condition. An 18-month-old boy was referred for evaluation of progressive bilateral gynecomastia and appearance of pubic hair. The patient had elevated plasma estradiol (349pg/ml) and testosterone (260ng/dl) levels that completely suppressed FSH and LH levels, and was subsequently diagnosed with an adrenal tumor on the right side. After removal of a 300-g adenocarcinoma, gynecomastia regressed and essentially normal hormone levels were restored. Aromatase activity in the tumor tissue determined by the 3H-water method was 71.0-104.4pmol/min/mg protein. High levels of aromatase protein and mRNA in the tumor tissue were also demonstrated, while neither aromatase activity nor protein was detected in normal adrenal glands. To investigate the regulation of aromatase expression in the adrenal carcinoma, we examined the usage of alternate promoters responsible for aromatase gene transcription. In the present case, the amounts of aromatase mRNA utilizing gonadal types of exon 1c (I.3) and 1d (II) were significantly higher than those that using other exon 1s. This result suggested that the utilization of a gonadal-type exon 1 might be involved in the overproduction of aromatase in estrogen-secreting adrenal carcinoma.

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A 27-year-old woman who presented with a left thyroid nodule was found to have hyperthyroidism caused by a syndrome of inappropriate secretion of TSH. The levels of free T₃, free T₄ and TSH were 9.50pg/mL, 4.05ng/dL and 2.16μU/mL, respectively. Magnetic resonance imaging of the head revealed a pituitary macroadenoma. The TSH response to TRH stimulation was normal and responses of other anterior pituitary hormones to stimulation tests were also normally preserved. Administration of octreotide with iodine successfully reversed hyperthyroidism prior to total resection of pituitary adenoma, which was followed by hemithyroidectomy of the left thyroid five months later. Histologically, the resected pituitary adenoma was a TSH-producing adenoma (TSH-oma) and the thyroid nodule was a papillary adenocarcinoma. Serum TSH diminished to undetectable levels immediately following pituitary adenomectomy but gradually normalized over nine months. Coexistence of a TSH-oma with thyroid cancer is very rare and only two similar cases have previously been documented. This combination raises the possibility that TSH may be involved in tumorigenesis in the thyroid gland.

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IGF-I regulates cell growth, differentiation, and survival in many cultured nerve cell lines. The present study was undertaken in the human neuroblastoma cell line, SH-SY5Y, to elucidate whether there are differences in the IGF-dependent signal transduction pathways that stimulate proliferation compared to those that induce differentiation. Quiescent SH-SY5Y cells were treated with IGF-I in the presence or absence of PD98059 (an inhibitor of MEK, a MAP kinase kinase) or LY294002 (an inhibitor of PI 3-kinase). Cell growth was assessed by measuring [³H]thymidine incorporation into DNA and cell number. Cell differentiation was assessed by measuring mRNA levels of NPY and neurite outgrowth. IGF-I both induced cell proliferation and differentiation. It stimulated tyrosine phosphorylation of the type I IGF receptor (IGF-IR) β-subunit, IRS-1, IRS-2, and Shc, and these changes were associated with activation of Erk and Akt. PD98059 inhibited activation of Erk and LY294002 repressed activation of Akt in response to IGF-I, but did not affect tyrosine phosphorylation of the IGF-IR, IRS-1, IRS-2, or Shc. Each PD98059 and LY294002 inhibited IGF-I-dependent cell proliferation in a concentration-dependent manner. In contrast, each of these inhibitors only partially depressed NPY gene expression induced by IGF-I and slightly inhibited IGF-I-mediated neurite outgrowth; however, when both PD98059 and LY294002 were present, IGF-I-dependent NPY gene expression and neurite outgrowth were abolished completely. These results suggest that in these nerve cells, 1) the IGF-I signals through the MAP kinase pathway and PI-3 kinase pathway are independently essential to induce IGF-I-dependent growth, and 2) alternate activation of the MAP kinase pathway and PI 3-kinase pathway is sufficient for the cells to undergo IGF-I-dependent differentiation.

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Proliferative response of peripheral blood mononuclear cells (PBMC) to glutamic acid decarboxylase (GAD), which has been reported in patients with type 1 diabetes, was measured in type 2 diabetes, especially in patients with antibodies to GAD initially diagnosed as having type 2 diabetes (anti-GAD⁺ type 2 diabetes). We studied 12 patients with type 1 diabetes, 22 with anti-GAD⁺ type 2 diabetes, 31 with type 2 diabetes who were negative for anti-GAD (anti-GAD^- type 2 diabetes), and 30 healthy control subjects for cellular responses in vitro to GAD. The mean stimulation index (SI) in response to GAD was significantly higher in type 1 diabetes than in anti-GAD^- type 2 diabetes or healthy controls (1.47±0.35 vs. 1.11±0.35, P<0.05, and 1.06±0.07, P<0.05, respectively). The mean SI in response to GAD in anti-GAD⁺ type 2 diabetes was significantly higher than in healthy controls (1.36±0.50 vs. 1.06±0.07, P<0.05). In anti-GAD⁺ type 2 diabetes, the mean SI in response to GAD was significantly higher in patients with alleles susceptible to type 1 diabetes (HLA-DRB1 *0405 and 0901) than those without susceptible alleles (1.55±0.60 vs. 1.12±0.16, P<0.05). All but one patient with a positive response to GAD had developed insulin deficiency (P<0.01 vs. nonresponders). In conclusion, we observed a significantly greater proliferative response to GAD in patients with anti-GAD⁺ type 2 diabetes, especially those with alleles susceptible to type 1 diabetes, and those responses may be a useful predictive marker for later development of insulin deficiency in anti-GAD⁺ type 2 diabetes.

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It is established that disproportionately elevated plasma proinsulin levels occur in patients with Type 2 diabetes. In the present study, multivariate analysis was performed to determine what factors contributed to the disproportionately elevated plasma proinsulin levels in Japanese patients with Type 2 diabetes (n=276). Results from univariate analysis showed that both fasting proinsulin/C-peptide ratio and proinsulin/IRI ratio were approximately 2-fold higher in patients with Type 2 diabetes than those in healthy nondiabetic subjects (n=45). In patients with Type 2 diabetes, both proinsulin/C-peptide ratio and proinsulin/IRI ratio were significantly positively correlated with fasting plasma glucose level (FPG) and HbA_1c. Neither proinsulin/C-peptide ratio nor proinsulin/IRI ratio was significantly correlated with BMI. Sulfonylurea-treated subjects had a significant elevation in both proinsulin/C-peptide ratio and proinsulin/IRI ratio compared with diet-treated subjects, whereas nonsulfonylurea hypoglycemic agent-treated subjects did not. Multivariate analysis confirmed that sulfonylurea treatment and FPG were significant determinants of both fasting proinsulin/C-peptide ratio (P=0.006 and P=0.030, respectively) and proinsulin/IRI ratio (P=0.003 and P=0.016, respectively) in patients with Type 2 diabetes. These results imply that disproportionate hyperproinsulinemia may reflect an excessive overwork of β cells under chronic sulfonylurea treatment as well as hyperglycemia.

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Basement membrane, a thin extracellular matrix, promotes tissue integrity and differentiated phenotype. This study was performed in order to investigate the effect of basement membrane components on adrenocorticotropin (ACTH) synthesis and to observe its relationship with cell morphology. Rat anterior pituitary cells were cultured on plastic culture plate coated with either Matrigel or poly-D-lysine. Phase-contrast microscopy and scanning electron microscopy showed that cells cultured on Matrigel appeared as a three-dimensional glandular-like cell aggregate, while those cultured on plastic showed a flat, confluent monolayer. Reverse-transcription polymerase chain reaction (RT-PCR) and Northern blot analysis revealed that ACTH synthesis in the Matrigel culture was not significantly different from that in the plastic culture. Our results suggest that the relationship between the morphological changes caused by cell-substrate interaction and pituitary hormone synthesis does not exist in all pituitary cell types and that other factors associated with cell-substrate interaction influence the hormone synthesis of some pituitary cells.

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Familial male-limited precocious puberty (FMPP) is a rare disease caused by constitutively activating mutations in the luteinizing hormone receptor (LH-R) gene. In the present study, we analyzed the LH-R gene in members of a Japanese FMPP family. Two males of the family were affected and had a heterozygous M398T mutation; one patient developed pubertal signs as early as 2 years of age, and the other at 6 years of age. Both patients had elevated serum testosterone levels and prepubertal gonadotropin secretions. The father of the latter patient carried the M398T mutation, but lacked history of precocious puberty. Thus, phenotypic differences were observed in the three males with the same LH-R mutation belonging to the same family. In summary, we have described a Japanese family with FMPP.

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A 45-year-old women with chronic idiopathic thrombocytopenic purpura was given monthly injections of the GnRH agonist leuprolide acetate for the treatment of uterine leiomyoma. Two weeks after the fifth injection, she showed mild symptoms of thyrotoxicosis. At that time, serum thyroxin (T4) and triiodothyronine (T3) levels were elevated whereas TSH level was suppressed. Anti-thyroglobulin (anti-Tg) and anti-thyroid peroxidase (anti-TPO) antibodies were positive, whereas TSH binding inhibitory immunoglobulin (TBII) was undetectable. Two months later, serum T4 and T3 levels spontaneously decreased below the normal ranges. Five months after the onset of the disease, they returned to normal without any treatment. Anti-TPO and anti-Tg antibodies gradually decreased during the clinical course. Thus, the present case was indicated to be an instance wherein silent thyroiditis developed after leuprolide acetate administration. This is the first report to demonstrate the association of thyroid disorder with leuprolide injection.

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The patient was a 32-year-old obese woman with a history of type 2 diabetes and hypertension for 6 years. Although she was treated with antihypertensive agents and intensive insulin therapy, her hyperglycemia was difficult to control. She wanted to have a baby but pregnancy was not recommended because her diabetes was under poor control and the use of antihypertensive medication. To achieve good control of obesity, diabetes and hypertension, she was admitted to our clinical department for weight reduction using very low calorie diet (VLCD). During VLCD she had a 19.8kg reduction in body weight and her blood glucose and blood pressure were in good control without the use of drugs. Five months later, she became pregnant after the fourth trial of intrauterine insemination (IUI) and gave birth to a female baby under insulin therapy. This is the first report that showed the usefulness of VLCD for prepregnant control of glucose metabolism and blood pressure in an obese hypertensive patient with type 2 diabetes mellitus.

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We encountered a case with long-term remission of Cushing's disease due to pituitary apoplexy. The apoplexy of pituitary adenoma secreting adrenocorticotropin hormone was diagnosed by successive and timely magnetic resonance imaging when the symptoms of the patient were not yet severe and anterior pituitary dysfunction was only a transient reduction of growth hormone secretion. Seven years after the first episode of pituitary apoplexy, hypercorticism recurred, and pituitary magnetic resonance imaging showed a regrowth of the pituitary adenoma. A spontaneous remission of Cushing's disease without significant visual, neurologic or hormonal defects seems to be a much more common phenomenon than has been previously suggested. Cases with relapse after spontaneous remission of Cushing's disease are rare and the duration of remission in previous reports was within 5 years. We observed such a patient with a 7 year-remission caused by pituitary apoplexy. We consider that a careful long-term follow-up is required for patients with Cushing's disease whose remission was due to pituitary apoplexy.

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Dehydroepiandrosterone (DHEA) is known to improve hyperglycemia of diabetic C57BL/KsJ-db/db mice that are obese and insulin resistant. In a previous study, we reported that DHEA as well as troglitazone suppresses the elevated hepatic gluconeogenic enzymes, glucose-6-phosphatase (G6Pase) and fructose-1, 6-bisphosphatase (FBPase) activities in C57BL/KsJ-db/db mice. In the present study, we evaluated the changes in mRNA of G6Pase and FBPase in db/db mice. Despite hyperinsulinemia, the G6Pase mRNA level of db/db mice was elevated as compared to their heterozygote littermate db/+m mice. In contrast, the FBPase mRNA level was not elevated in db/db mice. Administration of DHEA for two weeks significantly decreased the blood glucose level and the elevated G6Pase mRNA level in db/db mice. No significant changes were seen in the FBPase mRNA level after the administration of DHEA. Administration of troglitazone also decreased the blood glucose and G6Pase mRNA level in db/db mice although no changes were seen in the FBPase mRNA level. These results suggest that the elevation of G6Pase mRNA is important in elucidating the cause of insulin resistance, and that the G6Pase gene is at least one target for the hypoglycemic effects of DHEA as an insulin sensitizing agent in db/db mice.

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