Abstract:
:A patch-clamp study was conducted on cultured frog pituitary melanotrophs, in order to investigate the effects of adrenaline on the electrical activity of these cells. In the whole-cell configuration, adrenaline (1 microM) caused hyperpolarization that was accompanied by a fall in membrane input resistance and a blockage of spontaneous action potentials. Under voltage clamp, adrenaline elicited a net-outward current. The hyperpolarization became undetectable at a command voltage of -100 mV which corresponded to the equilibrium potential of potassium ions. The effect of adrenaline on membrane potential and spontaneous activity was blocked by the alpha 2-adrenergic receptor antagonist yohimbine (1-10 microM) but could not be mimicked by the alpha 2-adrenergic agonist clonidine (1-10 microM). In the cell-attached configuration, exposure of the extra-patch membrane to adrenaline increased the occurrence of single-channel currents with a slope conductance of 100 pS. The deduced reversal potential of these currents corresponded to the equilibrium potential of potassium ions. These results suggest that frog melanotrophs display an alpha 2-adrenergic receptor subtype coupled to potassium channels involved in hyperpolarization.
journal_name
Neuroendocrinologyjournal_title
Neuroendocrinologyauthors
Valentijn JA,Vaudry H,Cazin Ldoi
10.1159/000126633subject
Has Abstractpub_date
1994-01-01 00:00:00pages
20-8issue
1eissn
0028-3835issn
1423-0194journal_volume
59pub_type
杂志文章abstract::Phase relation between plasma corticosterone and locomotor activity rhythms was analyzed in individual rats with selective lesions of suprachiasmatic nuclei (SCN). SCN in Wistar male rats were selectively coagulated electrically and the extent of SCN destruction was examined histologically. Spontaneous locomotor activ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123200
更新日期:1981-07-01 00:00:00
abstract::An enriched population of cells immunoreactive to antiserum against S-100 protein, a marker of folliculo-stellate (FS) cells in the rat pituitary, was obtained by separation of dispersed pituitary cells from adult female rats by gradient sedimentation at unit gravity. The effect of FS cells on the stimulation and inhi...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125146
更新日期:1989-04-01 00:00:00
abstract::In the Siberian hamster the pituitary content of bioassayable MSH has been shown to be seasonally variable, being greater during the long days of spring and summer than during the short days of autumn and winter. Similar changes in the pituitary content of both bioassayable MSH and immunoreactive alpha MSH can be indu...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123019
更新日期:1980-05-01 00:00:00
abstract::Hypothalamic dopamine (DA) tonically inhibits prolactin (PRL) release from the anterior pituitary gland. Transient escapes from this DA tone elicit a pronounced potentiation of the PRL-releasing action of secretagogues such as thyrotropin-releasing hormone (TRH). Previous evidence has suggested that modulation of Ca(2...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000054456
更新日期:1999-07-01 00:00:00
abstract::Acute immobilization stress results in changes in the concentration of both dopamine and noradrenaline in specific forebrain limbic system areas, whereas the adrenaline levels remain unchanged. Changes in dopamine concentrations are more restricted than those in noradrenaline concentrations. Dopamine levels are increa...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123413
更新日期:1982-11-01 00:00:00
abstract::To study the role of the hypothalamus in the regulation of growth hormone (GH) synthesis, the rate of amino acid incorporation into GH in vitro was examined in rats with anterolateral deafferentation of the medial basal hypothalamus. Amino acid incorporation into GH (GH synthesis) decreased significantly 7 days after ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124946
更新日期:1988-05-01 00:00:00
abstract::The hypothalamic GnRH pulse generator activity, which was assessed by the characteristic increases in the multiple unit activity (MUA) specifically associated with the pulsatile LH secretion (MUA volleys), was monitored throughout the estrous cycle of the female goat. Blood samples were collected daily for analysis of...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127051
更新日期:1995-12-01 00:00:00
abstract::It is not known where melatonin acts to influence the neuroendocrine axis of seasonally breeding mammals. However, since the pars tuberalis (PT) contains the highest density of melatonin receptors, this adenohypophyseal subdivision is a potential target. Gonadotropes are the only immunocytochemically detectable adenoh...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127247
更新日期:1997-10-01 00:00:00
abstract::The effects of acute stress exposure upon cholecystokinin (CCK) and substance P (SP) concentrations in discrete hypothalamic regions of the adult male rat brain were studied. Animals were exposed to foot shock stress for periods of 2, 4, 10, 30 or 60 min duration; immediately afterwards they were decapitated; brains w...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124799
更新日期:1987-06-01 00:00:00
abstract::The feedback effect of systemically administered dexamethasone on basal plasma corticosterone levels and on adrenocortical responses to ether plus skin incision stress were studied in intact rats and in animals with bilateral dorsal or ventral hippocampectomy or fimbria section. It was found that in rats with ventral ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122974
更新日期:1980-01-01 00:00:00
abstract::An influence of thyroid status on the secretory activity of hypothalamic dopaminergic neurons was observed in adult rats and its involvement in the regulation of prolactin (PRL) secretion was examined. The secretory activity of the tuberoinfundibular dopaminergic (TIDA) neurons was evaluated by measurement of dopamine...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124797
更新日期:1987-06-01 00:00:00
abstract::The polyphenol curcumin (diferuloylmethane) is the active componenet of the spice plant Curcuma longa and has been shown to exert multiple actions on mammalian cells. We have studied its effect on folliculostellate (FS) TtT/GF mouse pituitary cells, representative of a multifunctional, endocrine inactive cell type of ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000287236
更新日期:2010-01-01 00:00:00
abstract::17 alpha-hydroxyprogesterone (up to 200 mug/day) and 11 beta-hydroxyandrostenedione (up to 500 mug) had no effect on PMS-induced ovulation in intact immature rats. 10 mug/day of testosterone propoinate (TP) on days 28-30 of life decreased the percent of animals ovulating and the number of ova produced; this effect per...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122338
更新日期:1975-01-01 00:00:00
abstract::Male Turkish hamsters received horizontal knife cuts within the hypothalamus to investigate the role of afferent and efferent projections of the paraventricular nucleus (PVN) in seasonal regulation of endocrine function. Following surgery, the animals were exposed to either a long (16 h light/8 h dark) or a short (8 h...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126159
更新日期:1992-04-01 00:00:00
abstract::The purpose of the present study was to evaluate the opioid receptor subtype mediating opioid modulation of growth hormone (GH) secretion during ontogeny. The mu-agonist morphine and the kappa agonist U50,488 caused a stimulation and inhibition of GH secretion, respectively, on postnatal day 10. Studies on postnatal d...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127077
更新日期:1996-06-01 00:00:00
abstract::In the Djungarian hamster Phodopus sungorus, the daily temporal pattern of synthesis and release of pineal hormone melatonin, mainly the length of the period of elevated melatonin levels, may be involved in transferring the information on day length to the neuroendocrine-gonadal axis. The present study investigated th...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123895
更新日期:1984-03-01 00:00:00
abstract::The accuracy and reproducibility of the World Health Organization (WHO) 2015 classification of bronchopulmonary neuroendocrine neoplasms (BP-NENs) is disputed. The aim of this study is to classify and grade BP-NENs using the WHO 2019 classification of digestive system NENs (DiS-NEN-WHO 2019), and to analyze its accura...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000502776
更新日期:2020-01-01 00:00:00
abstract::Adenylate cyclase activity was studied in anterior pituitary homogenates from young adult (6 months) and old (20 and 24 months) male rats. Basal, NaF-, GTP-, 5'-guanylimidodiphosphate (Gpp(NH)p)- and forskolin-stimulated activities were similar in the three groups, implying that the stimulatory guanyl nucleotide regul...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124682
更新日期:1986-01-01 00:00:00
abstract::The mammalian pineal gland appears to be a major endocrine component in the regulation of photoperiodic responses. The circadian pattern of secretion of the pineal hormone, melatonin, is regulated by the nervous system. Changes in photoperiod, acting via the nervous system, alter the temporal pattern of melatonin secr...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123579
更新日期:1983-11-01 00:00:00
abstract::The concentrations in plasma of the biologically active endogenous peptide Tyr-MIF-1 (Tyr-Pro-Leu-Gly-NH2) have not been measured during development or in female rats. By radioimmunoassay, we found that Tyr-MIF-1-like immunoreactivity (Tyr-MIF-1-LI) was first consistently detectable in plasma when the rat was 5 days o...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126322
更新日期:1992-12-01 00:00:00
abstract::Neuroanatomical attempts have been made to determine the synapses between luteinizing hormone-releasing hormone (LHRH)-containing neurons and substance P (SP)-containing neurons in the hypothalamus of female rats. Wheat germ agglutinin was injected into the septo-preoptic area (SPA) and found to be incorporated into c...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125724
更新日期:1991-03-01 00:00:00
abstract:BACKGROUND:Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) express insulin-like growth factor (IGF)-related factors [IGF1, IGF2; insulin receptor (IR)-A, IR-B; IGF-binding protein (IGFBP) 1-3] as well as somatostatin (SSTRs) and dopamine D2 receptors (D2Rs). OBJECTIVES:To (1) compare mRNA expression of IGF-rel...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000444280
更新日期:2016-01-01 00:00:00
abstract::Hypertension in male and aging female rodents is associated with glutamate-dependent plasticity in the hypothalamus, but existing models have failed to capture distinct transitional menopausal phases that could have a significant impact on the synaptic plasticity and emergent hypertension. In rodents, accelerated ovar...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000446073
更新日期:2017-01-01 00:00:00
abstract::The effects of corticotropin-releasing factor (CRF) on GnRH release from the adult male rat mediobasal hypothalamus (MBH) and median eminence (ME) were studied in an in vitro incubation system. CRF induced a dose-related inhibition of GnRH release from both the MBH and the isolated ME, and this inhibition was blocked ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124578
更新日期:1986-01-01 00:00:00
abstract::The effects of adrenalectomy (ADX) and dexamethasone (DEX) treatment on brain dopamine (DA) receptors of ovariectomized (OVX) rats were investigated by autoradiography using binding of the D1 and D2 antagonists ligands [3H]SCH 23390 and [3H]spiperone, respectively. Fourteen days after ADX, D1 receptors decreased in th...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126158
更新日期:1992-04-01 00:00:00
abstract::Interactions between the hypothalamic-pituitary-adrenocortical (HPA) system and melatonin secretion have been demonstrated, but only the effects of melatonin on the activity of the HPA system have been studied in man. Alterations of melatonin secretion described as low-melatonin syndrome have been demonstrated in pati...
journal_title:Neuroendocrinology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1159/000127186
更新日期:1997-04-01 00:00:00
abstract::Pierre Marie coined the term 'acromegaly' in 1886 and linked it to a distinct clinical disease with a characteristic clinical picture. However, Pierre Marie was not the first physician to give a full record of the clinical picture of acromegaly; others had preceded him, like the Dutch physician Johannes Wier. After Ma...
journal_title:Neuroendocrinology
pub_type: 杂志文章,评审
doi:10.1159/000371808
更新日期:2016-01-01 00:00:00
abstract::During adult-onset peripheral hypothyroidism, the brain maintains normal levels of thyroid hormone for some time through a mechanism of 'central homeostasis'. Although onset, duration, and termination of such a homeostatic phenomenon have been recently evaluated in rat models, the mechanism behind remains unknown. Dur...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000107580
更新日期:2007-01-01 00:00:00
abstract::Immunoreactive thyroid-stimulating hormone (IR-TSH) has been detected in the hypothalamus and is released in vitro by a calcium-dependent mechanism when the tissue is depolarized. Recently, immunocytochemical studies have revealed that IR-TSH is present in thyrotropes in the pars tuberalis. Therefore, because these th...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124149
更新日期:1985-07-01 00:00:00
abstract::It is now well documented that various polyclonal antisera to the human growth hormone-releasing factor (hGHRF, somatocrinin) visualize in the brain by immunohistochemistry the classical hypothalamic hypophysiotropic neurons and also antigens present in otherwise characterized peptidergic neuronal systems. The nature ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125370
更新日期:1990-04-01 00:00:00