Abstract:
:The effects of acute and chronic administration of a combination of lynestrenol-mestrenol, a widely employed contraceptive medication, on the dopaminergic system of the rat forebrain and striatum were investigated to better understand the biochemical basis of the neurological side-effects of steroid contraceptive drugs (SCDs). Both acute and chronic treatment increased the disappearance rate of striatal dopamine (DA) after synthesis blockade with alpha-methyl-p-tyrosine (alpha-MpT). Moreover, the conversion of 3H-tyrosine (3H-T) into 3H-DA was increased in the forebrain and striatum after chronic administration of this steroid combination. In the same animals, the utilization of tyrosine (T) is increased. :The effects of acute (4 days) and chronic (30 days) administration of a combination of lynestrenol-mestranol on the dopaminergic system of the rat forebrain and striata were studied. Mature female Sprague-Dawley rats were used. The dosage most often used was a 5: to .3 mg ratio/kg of body weight given orally. The last dose was given 24 hours before sacrifice. IV injection of tritiated-tyrosine was given at a dose of 1 mCi/kg. Animals were sacrificed at 10 and 25 minutes after injection; brains were removed and tissues immediately frozen and kept until assayed. Polyethylene cannulae were implanted into the lateral brain ventricles 72 hours before the injection of the labeled amino and tyrosine, dissolved in Ringer's solution, at a dose of 7 microCi in each ventricle. These animals were sacrificed and the striata kept frozen. Rats received alpha-methyl-p-tyrosine-methyl ester, 200 mg/kg iv. In each group 4 animals were sacrificed before treatments and at 1, 2, and 4 hours after this inhibitor was administered. Both acute and chronic treatments increased the disappearance rate of striated dopamine (DA) after the synthesis blockade with alpha-methyl-p-tyrosine. This effect may have been present in other areas of the brain also. The conversion of tritiated-tyrosine into tritiated-DA was increased in the forebrain and striatum after the chronic administration of the compound. In these animals the utilization of tyrosine was increased.
journal_name
Neuroendocrinologyjournal_title
Neuroendocrinologyauthors
Algeri S,Ponzio F,Dolfini E,Jori Adoi
10.1159/000122643subject
Has Abstractpub_date
1976-01-01 00:00:00pages
343-51issue
4eissn
0028-3835issn
1423-0194journal_volume
22pub_type
杂志文章abstract::Corticosterone (CORT) can alter several electrophysiological properties in the hippocampus. Few studies have reported the effects of CORT on hippocampal long-term potentiation (LTP). In the CA1 region of the hippocampal slice, we studied the relative increase in population spike (PS) amplitude after inducing tetanus (...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126717
更新日期:1994-07-01 00:00:00
abstract::Single rat neurohypophyses were impaled on a platinum electrode, perifused with isotonic medium and fractions of perifusate collected each minute. Arginine vasopressin content of the fractions was measured by radioimmunoassay. The basal release of arginine vasopressin varied from 50 to 350 pg (0.02-0.14 mU/min) betwee...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123248
更新日期:1981-11-01 00:00:00
abstract:INTRODUCTION:The pituitary gland has a high expression of somatostatin receptors (SSTRs) and is therefore a potential organ at risk for radiation-induced toxicity after 177Lu-DOTATATE treatment. OBJECTIVE:To study changes in pituitary function in patients with neuroendocrine tumors (NETs) treated with dosimetry-based ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000507761
更新日期:2020-04-08 00:00:00
abstract::The present study investigated the effects of short-term exposure to constant light, initiated at the time of ovariectomy, on the ability of estradiol (E2) treatment alone or in conjunction with progesterone (P) to induce afternoon surges of LH and prolactin (PRL). Adult Fischer 344 rats, which had been ovariectomized...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127009
更新日期:1995-09-01 00:00:00
abstract:CONTEXT:Early pubertal luteinizing hormone (LH), and by inference gonadotropin-releasing hormone (GnRH), pulse secretion is marked by high nocturnal but low daytime frequency; however, the underlying mechanisms remain unclear. Plasma concentrations of progesterone, the major regulator of GnRH frequency in women, increa...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000336395
更新日期:2012-01-01 00:00:00
abstract::Previous studies have shown that neonatal administration of monosodium glutamate (MSG) results in a clearly defined lesion of the arcuate nucleus which disrupts mechanisms regulating normal FSH but not LH secretion in the adult female hamster. The present study was designed to investigate the effects of neonatally adm...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123296
更新日期:1982-03-01 00:00:00
abstract::Amygdalotomized, sham-operated and intact wild-derived house mice of both sexes were group-caged (8-10) or singly caged for 3 weeks. The weights of ovaries (p is less than 0.05) and uteri (p is less than 0.01) were less in intact and sham-operated grouped females compared to singly caged intact and amygdalotomized fem...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122731
更新日期:1978-01-01 00:00:00
abstract:INTRODUCTION:Pituitary neuroendocrine tumors (PitNETs), the most abundant of all intracranial tumors, entail severe comorbidities. First-line therapy is transsphenoidal surgery, but subsequent pharmacological therapy is often required. Unfortunately, many patients are/become unresponsive to available drugs (somatostati...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000505923
更新日期:2020-01-01 00:00:00
abstract::The neurohypophysial peptide hormone [Arg8]vasopressin (AVP) has well documented pressor effects in the periphery. These are mediated by vasopressin receptors (VPRs) of the V1a subtype, expressed by vascular smooth muscle cells, which induce vascular contraction when activated. AVP also has effects on the vasculature ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127060
更新日期:1995-12-01 00:00:00
abstract::The release of the decapeptide gonadotropin-releasing hormone (GnRH) from neuroterminals in the median eminence varies depending upon the stage of development, time of day, reproductive season, and day of the ovarian cycle. With respect to the biosynthetic events responsible for such alterations in GnRH release, we ha...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000054373
更新日期:1998-10-01 00:00:00
abstract::Introduction Dysregulation of the mTORC1-dependent pathways in pancreatic neuroendocrine neoplasms (PanNENs) underlies the introduction of the mTORC1 inhibitor everolimus as treatment of advanced progressive PanNENs. Although everolimus significantly increases progression free survival, most patients acquire secondary...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000509865
更新日期:2020-07-02 00:00:00
abstract::An abolishment of 24 h periodicity of the adrenocortical activity was observed in rats subjected to a prolonged food deprivation of 7--8 days. Total locomotor activity progressively decreased and its circadian rhythm faded out in a similar fashion as the adrenocortical rhythm. The circadian rhythms of both locomotor a...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122924
更新日期:1979-01-01 00:00:00
abstract::The reuptake of dopamine into nerve terminals is the primary mechanism of inactivation of this neurotransmitter in the synaptic cleft. We report sex differences and estrous cycle variations of rat striatal dopamine uptake sites. During the estrous cycle, peak density of striatal dopamine uptake sites labelled with [3H...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126507
更新日期:1993-07-01 00:00:00
abstract::Galanin-like peptide (GALP) is a 60-amino-acid peptide with structural similarities to galanin and a high affinity for galanin receptors. GALP is expressed by a discrete population of neurons in the arcuate nucleus (ARC) and median eminence of the hypothalamus of several species, including the rat. GALP neurons expres...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000079752
更新日期:2004-01-01 00:00:00
abstract::In order to search for candidate genes related to pituitary adenoma aggressiveness, the present investigation was intended to compare the mRNA expression profile from a pool of four nonfunctional pituitary adenomas (NFPA) with a spinal cord metastasis of a nonfunctional pituitary carcinoma (MNFPC). The metallothionein...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000092521
更新日期:2005-01-01 00:00:00
abstract:BACKGROUND:Kisspeptins are recognized as important stimulators of gonadotropin-releasing hormone (GnRH) and gonadotropin secretion. In sheep, the nonbreeding (anestrous) period is characterized by reduced Kiss1 mRNA expression in the hypothalamus. The aim of the present study was to determine whether the response to ki...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000227806
更新日期:2009-01-01 00:00:00
abstract::Pituitary adenylate cyclase-activating polypeptide (PACAP) receptors were characterized and their function investigated in mouse pituitary neurointermediate lobe explants. We show that mouse neurointermediate lobes can be maintained for up to 1 month in defined medium. After 8 days in culture, these explants are devoi...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127091
更新日期:1996-07-01 00:00:00
abstract::A number of neurochemical messengers have been shown to act directly on the melanotrope cells of the pars intermedia of Xenopus laevis to regulate alpha MSH secretion. In the present study the possibility that the melanotropes are also indirectly controlled has been examined. For this purpose, the characteristics of a...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125853
更新日期:1991-07-01 00:00:00
abstract::We have attempted to elucidate the effect of glucose concentrations on the release of thyrotropin-releasing hormone (TRH), a brain neuropeptide possessing glucoregulatory function, from rat hypothalamic slices in vitro. Rat hypothalamic slices were preincubated for 60 min at 37 degrees C in Krebs-Ringer bicarbonate (K...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125751
更新日期:1991-04-01 00:00:00
abstract::In previous studies we obtained evidence that serotonin release by p-chloroamphetamine (PCA) causes an increase in corticosterone secretion but that this effect is not mediated via the raphe nuclei in the midbrain. In contrast, PCA-induced prolactin secretion was abolished by dorsal raphe lesions. In the present study...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124205
更新日期:1985-11-01 00:00:00
abstract:INTRODUCTION:An increasing number of middle-aged men are being screened for low testosterone levels and the number of prescriptions for various forms of testosterone replacement therapy (TRT) has increased dramatically over the last 10 years. However, the safety of TRT has come into question with some studies suggestin...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000504445
更新日期:2020-01-01 00:00:00
abstract::We determined the effect of 17 beta-estradiol (E2) on synthesis and release of luteinizing hormone (LH) induced by drugs which activate intracellular signal transduction mechanisms in rat anterior pituitary cells. Cells were pretreated with E2 (6 x 10(-10) M) or diluent for 24 h, then washed and incubated for 4 h with...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125405
更新日期:1990-06-01 00:00:00
abstract::Thymic neuroendocrine neoplasms are rare tumours, but their management can often be highly problematic. While previously assumed to be essentially variants of bronchopulmonary (lung) carcinoids, they are generally more aggressive and more difficult to treat. Some 25% are associated with multiple endocrine neoplasia-1,...
journal_title:Neuroendocrinology
pub_type: 杂志文章,评审
doi:10.1159/000472255
更新日期:2017-01-01 00:00:00
abstract::Neuronal nitric oxide synthase, e.g. NADPH diaphorase (NADPH-d), catalyzes formation of the free radical, nitric oxide (NO), and occurs within brain structures that have functional significance for energy fuel homeostasis. The following studies examined whether populations of NADPH-d-positive neurons in the hypothalam...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000054417
更新日期:1999-03-01 00:00:00
abstract::Estradiol (E2) and progesterone (P4) interact to influence tuberoinfundibular dopaminergic neuronal activity and contribute to the control of prolactin (PRL) release. This study examined tyrosine hydroxylase mRNA signal levels in the arcuate nucleus of the hypothalamus and tyrosine hydroxylase activity in the stalk-me...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126583
更新日期:1993-11-01 00:00:00
abstract::The effect of intravertebral infusion of angiotensin II on cardiac vagal efferent activity was studied in anesthetized mongrel dogs. Unilateral infusion of doses of angiotensin II as low as 5 ng/kg/min inhibited basal vagal tone and also decreased the slope of the relationship between cardiac vagal efferent activity a...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124120
更新日期:1985-06-01 00:00:00
abstract::Arginine-vasopressin (AVP) is regarded as a potent stimulator of pituitary adrenocorticotropin (ACTH) secretion and participates therefore in the regulation of the hypothalamic-pituitary-adrenal (HPA) axis function in concert with the physiological activator of the axis, hypothalamic corticotropin-releasing hormone (C...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126787
更新日期:1994-11-01 00:00:00
abstract::The present study was undertaken in order to better characterize the functional state of anterior pituitary gland in young and old rats by using prolactin secretion and incorporation of radioactive phosphate into phosphatidylinositol (PI) as markers. The in vitro incorporation of radiolabeled phosphate into anterior p...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124714
更新日期:1987-02-01 00:00:00
abstract::The arcuate nucleus-median eminence complex (AM) undergoes major structural and functional changes during normal puberty or if exposed to a pulse of estradiol in the prepuberal period. Those changes are expressed by increased synaptogenesis and by a drastic alteration in the feedback control of anterior pituitary glan...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124775
更新日期:1987-06-01 00:00:00
abstract::Visual average evoked responses (AERs) to 4 intensities of light were studied in 5 patients with adrenal cortical insufficiency. Patients were tested off all medications, on ACTH while off all medications, and during replacement with carbohydrate-active steroids. Off treatment, when steroid levels were low, AERs were ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122452
更新日期:1975-01-01 00:00:00