Methylphenidate (MPH) is the most preferred drug for treatment of the attention deficit hyperactivity disorder (ADHD). Here, we aimed to discuss the possible effects and mechanisms of MPH on precocious puberty (PP) via a case series with seven children who had normal body mass index. In this case series we evaluated seven children with ADHD, who had received MPH for at least 6 months (0.5 mg/kg/dose three times a day, maximum 60 mg) and admitted to Department of Pediatric Endocrinology with PP symptoms. The mean age was 8.16 years. Basal hormonal levels (luteinizing hormone [LH], follicle stimulating hormone, and estrogen/testosterone) were within normal range. Results of LH-releasing hormone stimulation tests demonstrated central pubertal responses. Glutamine, dopamine and noradrenaline are most important excitatory neurotransmitters that have a role at the beginning of puberty. The effect of MPH, cumulating dopamine and noradrenaline in the synaptic gap could be associated with the acceleration of puberty with the excitatory effect of dopamine’s gonadotropin-releasing hormone (GnRH) release, excitatory effect of noradrenaline’s GnRH release and the disappearance of GnRH receptor expression suppressor effect on prolactin disinhibitory effect.
Acceleration ; Adolescent ; Attention Deficit Disorder with Hyperactivity ; Body Mass Index ; Child ; Dopamine ; Endocrinology ; Follicle Stimulating Hormone ; Glutamine ; Gonadotropin-Releasing Hormone ; Humans ; Methylphenidate ; Neurotransmitter Agents ; Norepinephrine ; Prolactin ; Puberty ; Puberty, Precocious ; Receptors, LHRH ; Reference Values

Congenital central hypothyroidism (C-CH) is a rare disease in which thyroid hormone deficiency is caused by insufficient thyrotropin (TSH) stimulation of a normally-located thyroid gland. Most patients with C-CH have low free thyroxine levels and inappropriately low or normal TSH levels, although a few have slightly elevated TSH levels. Autosomal recessive TSH deficiency and thyrotropin-releasing hormone receptor-inactivating mutations are known to be genetic causes of C-CH presenting in the absence of other syndromes. Recently, deficiency of the immunoglobulin superfamily member 1 (IGSF1) has also been demonstrated to cause C-CH. IGSF1 is a plasma membrane glycoprotein highly expressed in the pituitary. Its physiological role in humans remains unknown. IGSF1 deficiency causes TSH deficiency, leading to hypothyroidism. In addition, approximately 60% of patients also suffer a prolactin deficiency. Moreover, macroorchidism and delayed puberty are characteristic features. Thus, although the precise pathophysiology of IGSF1 deficiency is not established, IGSF1 is considered to be a new factor controlling growth and puberty in children.
Adolescent ; Cell Membrane ; Child ; Glycoproteins ; Humans ; Hypothyroidism* ; Immunoglobulins ; Infant, Newborn ; Neonatal Screening* ; Prolactin ; Puberty ; Puberty, Delayed ; Rare Diseases ; Thyroid Gland ; Thyrotropin ; Thyrotropin-Releasing Hormone ; Thyroxine

To produce milk, four secretory processes are synchronized in the alveolar cell of the mature, functional mammary gland: (1) exocytosis, (2) fat synthesis and secretion, (3) secretion of ions and water, and (4) transcytosis of immunoglubulins and other substances from the interstitial space. Milk is synthesized continuously into the alveolar lumen, where it is stored until milk removal from the breast is initiated. Prolactin mediates the central nervous system regulation of milk secretion, but its influence is modified greatly by local factors that depend on milk removal from the breast. Oxytocin mediates milk let-down by stimulating the contraction of myoepithelial cells that surround the alveoli and ducts. Lactogenesis includes all the processes necessary to go from the undifferentiated mammary gland in the early pregnant animal to full lactation sometime after parturition. The most important factors in initiation of lactogenesis stage II appear to be progesterone withdrawal. The metabolic demands of breastfeeding require an increase in maternal metabolism. Postpartum suppression of fertility is thought to be the result of an alteration in pulsatile gonadotropin releasing hormone secretion from the hypothalamus. Women who wish to ensure against pregnancy during lactation usually are advised to use other contraceptive means.
Animals ; Breast ; Breast Feeding ; Central Nervous System ; Contracts ; Dietary Sucrose ; Exocytosis ; Female ; Fertility ; Gonadotropin-Releasing Hormone ; Humans ; Hypothalamus ; Ions ; Lactation ; Mammary Glands, Human ; Milk ; Milk Ejection ; Oxytocin ; Parturition ; Postpartum Period ; Pregnancy ; Progesterone ; Prolactin ; Secretory Pathway ; Transcytosis ; Water

OBJECTIVETo investigate the incidence of abnormal karyotypes and Y chromosome microdeletion in Chinese men with azoospermia, and the relationship with reproductive hormones.

METHODSFour hundred and eighty nine cases of azoospermic patients and 20 fertile men were studied. Karyotypes and Y chromosome microdeletion were analyzed by G-banding and mutiplex polymerase chain reaction, respectively. Chemiluminescene immunoassay technique was applied to measure the serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), and prolactine (PRL).

RESULTSChromosome abnormalities were found in 102 out of 489 azoospermic patients (20.86%), among them 86 (84.31%) cases had sex chromosome abnormalities, with 73 cases being Klinefelter syndrome. Y chromosome microdeletions were detected in 58 (11.86%) cases out of the 489 patients, and deletion of the AZFc region was the leading group (63.8% of all deletions), followed by AZFbc (19.0%), AZFabc (10.3%), AZFb or AZFa (3.4%). FSH, LH levels were significantly increased and T level was decreased in azoospermic patients compared with the fertile men group (P<0.01). Furthermore, in the azoospermic patients with Klinefelter syndrome or AZFabc microdeletions, FSH and LH levels were increased more significantly, and were statistically different from azoospermic patients with normal karotype or without Y chromosome microdeletion (P<0.05).

CONCLUSIONIn the Chinese men with azoospermia, the incidence of abnormal karyotype and Y chromosome microdeletion were similar to those described previously in other populations. In azoospermia with Klinefelter syndrome or AZFabc microdeletions, FSH and LH levels increased markedly indicating the protracted stimulation of gonadotrophs due to lack of androgen feedback.

Adult ; Azoospermia ; blood ; genetics ; Case-Control Studies ; Chromosomes, Human, Y ; genetics ; Follicle Stimulating Hormone ; blood ; Genetic Association Studies ; Genetic Loci ; Humans ; Karyotyping ; Luteinizing Hormone ; blood ; Male ; Prolactin-Releasing Hormone ; blood ; Seminal Plasma Proteins ; genetics ; Sequence Deletion ; Testosterone ; blood

Adolescence is a transition period from childhood to adulthood, and many physical, cognitive, and psychosocial changes are taken place in adolescence. Endocrinologic changes are usually associated with puberty, and play a central role in accomplishing the developmental task of adolescence. During puberty, secretion of gonadotropins, gonadal steroids, growth hormone, insulin like growth factor-1 and inhibin are increased. Insulin resistance is transiently increased in puberty. Gender differences of some hormones, such as testosterone-binding globulin, prolactin, prostate specific antigen, leptin and adiponectin, appear during puberty. The activation of hypothalamic gonadotropin-releasing hormone pulse generator initiates and regulates the reactivation of hypothalamic-pituitary-gonadal axis at puberty. The adolescent growth spurt in normal girls and boys depends on both estradiol and growth hormone. In the male as well as the female, estrogen (not androgen) is the critical sex hormone in the pubertal growth spurt, skeletal maturation, and the accrual of peak bone mass.
Adiponectin ; Adolescent ; Axis, Cervical Vertebra ; Estradiol ; Estrogens ; Female ; Gonadotropin-Releasing Hormone ; Gonadotropins ; Gonads ; Growth Hormone ; Humans ; Hypogonadism ; Inhibins ; Insulin ; Insulin Resistance ; Leptin ; Male ; Mitochondrial Diseases ; Ophthalmoplegia ; Prolactin ; Prostate-Specific Antigen ; Puberty ; Steroids

A 45-year-old woman who complained of weight gain and irregular menstruation was diagnosed as having Cushing's syndrome due to a 3 cm sized left adrenal adenoma. She underwent left adrenalectomy, and she also underwent combined anterior pituitary tests before and 9 months after the surgery. The growth hormone and adrenocorticotropic hormone levels failed to respond to hypoglycemia before the surgery, but their responses recovered after the surgery. Cortisol and thyroid stimulating hormone failed to respond to hypoglycemia and thyrotropin releasing hormone (TRH) before the surgery, respectively, but these were improved after the surgery. Luteinizing hormone, follicle stimulating hormone, and prolactin adequately responded to gonadotropin-releasing hormone and TRH, respectively, before and after the surgery. However, the basal levels of these hormones were higher after adrenalectomy, suggesting that hypercortisolemia had a significant influence on all the pituitary hormones.
Adenoma* ; Adrenalectomy ; Adrenocorticotropic Hormone ; Cushing Syndrome* ; Female ; Follicle Stimulating Hormone ; Gonadotropin-Releasing Hormone ; Growth Hormone ; Humans ; Hydrocortisone ; Hypoglycemia ; Hypopituitarism ; Luteinizing Hormone ; Menstruation ; Middle Aged ; Pituitary Hormones ; Prolactin ; Thyrotropin ; Thyrotropin-Releasing Hormone ; Weight Gain

BACKGROUND: GH3 cells are a well characterized and widely used model used for the in vitro study of growth hormone (GH) secretion. Thyrotropin releasing hormone (TRH) binds to receptors belonging to the family of G protein-coupled receptors, and secrets both GH & prolactin. Phospholipase D (PLD) is an enzyme that hydrolyses phosphatidylcholine to yield phosphatidic acid and choline, and plays important roles in cellular proliferation and hormonal secretion. To elucidate the pathway of the action of TRH in GH3 cells, we investigated the activities of PLC and PLD in GH3 cells treated with TRH or phorbor 12-myristate 13-acetate (PMA). METHODS: GH3 cells were labeled with [3H] myristate, followed by incubation of with 0.3% ethanol, prior to before the addition of the agonists. The total lipids were extracted from the harvested cells following treatment with the agonists. The PLD activity was assessed by measuring [3H] phosphatidylethanol from the [3H] phospholipid using thin layer chromatography. RESULTS: TRH (1 muM) stimulated the PLC activity by 44-fold over that of the control values. TRH (1 microM), mastoparan (5 muM), and PMA (500 muM) for 30 minutes increased PLD activity by 1.9, 1.5 and 2.2 fold, respectively, in comparison to the controls. The PLD activities after 15, 30, 60, 120 and 240 min treatments of TRH (1 microM) were 142%, 170%, 172%, 160% and 115%, respectively. CONCLUSION: These results suggest that TRH stimulates not only the PLC activity, but also the PLD activity in GH3 cells.
Cell Proliferation ; Choline ; Chromatography, Thin Layer ; Ethanol ; Growth Hormone ; Humans ; Myristic Acid ; Phosphatidic Acids ; Phosphatidylcholines ; Phospholipase D* ; Phospholipases* ; Prolactin ; Thyrotropin-Releasing Hormone

OBJECTIVE: To assess the etiologic diagnosis of primary amenorrhea and review the clinical significance in management of primary amenorrhea. METHODS: To make the accurate etiologic diagnosis of primary amenorrhea, karyotype, hormone study (TSH, Prolactin, LH, FSH, Estradiol, Testosterone, DHEA-S), various imaging techniques were performed in total 57 patients. And additional GnRH stimulation test and bone densitometry were also performed in group of hypogonadotropic amenorrhea with normal sella and brain imaging for discriminating the hypothalamic and pituitary cause and in patients with low estrogenic state for identifying the risk of osteoporosis, respectively, then reviewed as to clinical significance according to etiologic classification, karyotypical abnormalities, and risk of osteoporosis in low estrogenic group. RESULTS: The range of age at diagnosis was from 13 to 34 years, most commonly, 17-18 years, 26.3%. The most common causes of primary amenorrhea was 46,XX ovarian failure and hypothalamic failure, 19.3% and 19.3%, respectively. The next common causes were genetic disorder related with Turner syndrome (17.5%), M llerian agenesis (12.3%), complete androgen insensitivity syndrome (10.5%), orderly. In cytogenetic study, 19 patients (34%) showed abnormal karyotype, of abnormal karyotypes, Turner genotype was most common (52%), and 46,XY was second most common (31.5%). Almost all patients with low estrogenic state showed osteopenia or osteoporosis. CONCLUSION: The most common causes of primary amenorrhea were 46,XX gonadal failure, hypothalamic failure, Turner syndrome. These all patients were at high risk of osteoporosis or osteopenia.
Abnormal Karyotype ; Amenorrhea* ; Androgen-Insensitivity Syndrome ; Bone Diseases, Metabolic ; Classification ; Cytogenetics ; Densitometry ; Diagnosis ; Estradiol ; Estrogens ; Female ; Genotype ; Gonadotropin-Releasing Hormone ; Gonads ; Humans ; Karyotype ; Male ; Neuroimaging ; Osteoporosis ; Prolactin ; Testosterone ; Turner Syndrome

BACKGROUND: ackground: Sheehan's syndrome secondary to severe postpartum hemorrhage is one of the major causes of pituitary insufficiency in Korea. Most of these patients do not manifest symptoms or signs of gross endocrinopathies. Earlier detection of pituitary insufficiency is of clinical importance. The combined pituitary stimulation test that uses the four hypothalamic releasing hormones is a rapid, safe, and effective way to evaluate anterior pituitary function. However, the criteria for a normal response has not been established in Korea. METHODS: Combined anterior pituitary stimulation tests were performed on fourteen healthy women who had no history of endocrine disease. Combined tests of anterior pituitary reserve were done no forty-five patients who suffered from massive postpartum hemorrhage which required transfusing, along with subsequent shock or changing consciousness and in thirty-nine patients who experienced mild postpartum hemorrhage. RESULTS: 1) In the severe hemorrhage group, thirty-three of forty-five women (73.3%) showed blunted responses in more than one of the anterior pituitary hormones in the combined pituitary stimulation tests. However, in the mild hemorrhage group, only eighteen of thirty-nine women (46.2%) demonstrated blunted responses of more than one of the anterior pituitary hormones. 2) In the severe hemorrhage group, the TSH response was blunted in twenty-five patients (55.6%), prolactin in eleven patients (24.4%), ACTH in ten patients (22.2%), LH in ten patients (22.2%), GH in nine patients (20%), and FSH in five patients (11.1%). 3) The results of combined pituitary stimulation tests in the normal control group were different from the results of other studies. CONCLUSION: It is recommended that the women who experienced a severe postpartum hemorrhage should be evaluated by using the combined pituitary stimulation test. Moreover, criteria for a normal response to the combined pituitary stimulation test should be established in Korea.
Adrenocorticotropic Hormone ; Consciousness ; Endocrine System Diseases ; Female ; Hemorrhage ; Humans ; Hypopituitarism ; Korea ; Pituitary Hormone-Releasing Hormones ; Pituitary Hormones, Anterior ; Postpartum Hemorrhage* ; Postpartum Period* ; Prolactin ; Shock

The workplace exposure of chemicals has steadily increased, therefore the concern for subsequent effect on reproductive outcome has been an important issue in occupational medicine. In previous studies, higher rates of spontaneous abortion, reduced fertility and menstrual disorder among women, and an impairment of sperm quantity and quality among men have been associated with a wide variety of chemical agents. This study was conducted to evaluate the effects of toluene, xylene and trichloroethylene (TCE) injection on the mRNA levels of GnRH, GnRH receptor and Pit-1 genes in male rats hypothalamus and pituitary and the effects on the plasma levels of FSH, LH, prolactin and testosterone. Sprague-Dawley male rats were divided into five groups of five each according to concentration of toluene, xylene and TCE. The rats were injected subcutaneously to 0, 50, 100, 200, 400 mg/kg body weight/day of toluene, xylene and TCE, respectively for 6 days. Rat brains were excised and hypothalamus and pituitary were separated. Reverse transcription-polymerase chain reaction (RT-PCR) and RNase protection assay (RPA) were used to evaluate the GnRH, GnRH receptor and Pit-1 mRNA levels. Plasma concentrations of FSH, LH, prolactin and testosterone were assayed by radioimulunoassay (RIA). The results were as follows; 1. GnRH, GnRH receptor and Pit-1 mRNA levels in toluene and xylene injected groups, and GnRH receptor mRNA levels in TCE injected group were lowered dose-dependently. Especially, GnRH receptor and Pit-1 mRNA levels in 200 mg/kg of toluene injected group, and GnRH, GnRH receptor and Pit-1 mRNA levels in 400 mg/kg of toluene injected group were significantly lowed than control group (p<0.05). GnRH receptor and Pit-1 mRNA levels in 400 mg/kg of xylene injected group, and GnRH receptor mRNA levels in 400 mg/kg of TCE injected group were significantly lower than control group (p<0.05). 2. The plasma levels of prolactin and testosterone in 400 mg/kg of toluene injected group, and LH in 100, 200 and 400 mg/kg of xylene injected group, and testosterone in 400 mg/kg of TCE injected group were significantly lower than control group (p<0.05). In conclusion, we speculated that toluene and xylene affected reproductive system secondarily through hypothalamus-pituitary axis, and TCE affected directly through steroidogenesis. And we recomended that further study for assessment of the reproductive toxiclty of mixed organic solvent exposures should be conducted.
Abortion, Spontaneous ; Animals ; Axis ; Brain ; Female ; Fertility ; Gene Expression* ; Gonadotropin-Releasing Hormone* ; Humans ; Hypothalamus* ; Male* ; Occupational Medicine ; Plasma ; Pregnancy ; Prolactin ; Rats* ; Rats, Sprague-Dawley ; Receptors, LHRH* ; Ribonucleases ; RNA, Messenger ; Spermatozoa ; Testosterone ; Toluene* ; Trichloroethylene* ; Xylenes*