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) between individual neurohypophyses. Recordings previously obtained from rat supraoptic neurones provided the patterns for electrical stimulation. 8-min segments of a phasically and a continuously firing neurone were selected such that each was firing at a mean rate of 6 spikes/s and possessed very similar overall distributions of interspike intervals. In 15 experiments individual neurohypophyses were stimulated with the phasic pattern, followed by the continuous pattern, or vice versa, separated by an 8-min unstimulated period. In either case, significantly more hormone was released during phasic stimulation than during continuous stimulation. It is concluded that the phasic firing pattern typical of vasopressin neurones is highly efficient for the release of vasopressin from the neurohypophysis, but that its effectiveness does not lie in an increased preponderance of short interspike intervals.
journal_name
Neuroendocrinologyjournal_title
Neuroendocrinologyauthors
Bicknell RJ,Leng Gdoi
10.1159/000123248subject
Has Abstractpub_date
1981-11-01 00:00:00pages
295-9issue
5eissn
0028-3835issn
1423-0194journal_volume
33pub_type
杂志文章abstract::We have investigated the variations in growth hormone (GH) and somatostatin (SOM) mRNAs in adult, middle-aged and aging rats of both sexes using quantitative in situ hybridization. cDNA probes complementary to GH mRNA and SOM mRNA were used on fixed pituitary and hypothalamic sections, respectively. A clear sexual dim...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125967
更新日期:1991-12-01 00:00:00
abstract::His-dTrp-Ala-Trp-dPhe,Lys-NH2(GHRP-6) is a synthetic compound that releases GH in a dose-response and specific manner in several species and that may well be related to an endogenous compound of similar structure. The aim of this study was to investigate the in vivo GH responses to GHRP-6 in pentobarbital anesthetized...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126366
更新日期:1993-01-01 00:00:00
abstract::Studies were undertaken to characterize the secretion of corticotropin-releasing factor (CRF) and arginine vasopressin (AVP) into the hypophysial-portal circulation of the conscious sheep. In addition, we examined the temporal relationship between the secretion of these two hypothalamic peptides and the secretion of t...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125141
更新日期:1989-04-01 00:00:00
abstract::The purpose of these studies was to determine the temporal requirements and time of day required for progesterone (P4) to amplify versus extinguish LH surges. The experimental animal model used in these studies was the 7-day ovariectomized rat (day 0) treated continuously with estradiol (E2) for 2-4 days (days 2, 3 or...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124241
更新日期:1986-01-01 00:00:00
abstract::Lactotrophs, gonadotrophs, thyrotrophs and somatotrophs of the rat anterior pituitary (AP) express 68-kDa neurofilaments (NF68) and other neuronal markers. NF68 expression in the AP appears to be estrogen-dependent, but its significance is unknown. The aims of this work were: (1) to establish the expression pattern of...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000095548
更新日期:2006-01-01 00:00:00
abstract:BACKGROUND:The reviewing and assessment of epidemiological characteristics of neuroendocrine tumours (NETs) remains a challenge. Despite the fact that it is an uncommon family of neoplasms, several worldwide series have revealed an increasing incidence of this rare condition. However, the data are difficult to compare ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000441897
更新日期:2017-01-01 00:00:00
abstract::The effect of sonicated suspensions of phosphatidylserine (PS), an acidic phospholipid, was investigated on prolactin secretion utilizing in vivo and in vitro approaches. Acute and chronic administration of PS reduced plasma prolactin levels during different phases of circadian rhythms. The phospholipid was able to in...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123261
更新日期:1981-12-01 00:00:00
abstract::The facilitation of sexual receptivity by oxytocin (OT) in female rats is related to the regulation of oxytocin receptors (OTR) by ovarian steroids in the ventromedial nuclei (VMN) of the hypothalamus. In a previous study, we have shown that estradiol benzoate (EB) causes a twofold increase in OTR binding in the VMN. ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126125
更新日期:1992-03-01 00:00:00
abstract::The following fragments of LHRH were administered intraventricularly and tested for their ability to enhance sexual receptivity in ovariectomized, estrogen-primed female rats: LHRH1-6 NH2, Ac-LHRH5-10, des-Tyr5-LHRH and des-Gly10-LHRH. LHRH1-6 NH2 had no effect on sexual behavior compared to saline-infused controls. A...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123503
更新日期:1983-06-01 00:00:00
abstract::The mechanisms involved in the activation of the hypothalamus-pituitary-adrenal axis after administration of Mycoplasma fermentans were examined. Male rats were injected intracerebroventricularly (i.c.v.) with heat-inactivated M. fermentas (6 micrograms protein/10 microliters/rat) or vehicle and were killed 2 h later....
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127241
更新日期:1997-09-01 00:00:00
abstract::To examine the role of excitatory amino acid neurotransmitters in the regulation of LH and FSH secretion in ovariectomized (ovx) adult rats treated with estradiol and progesterone, we measured the release rates of the excitatory amino acid neurotransmitters, glutamate and aspartate, as well as the neurally inactive am...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126673
更新日期:1994-04-01 00:00:00
abstract:BACKGROUND/AIM:The mode of action of the somatostatin analog octreotide on neuro-endocrine tumour proliferation is largely unknown. Overexpression of the proto-oncogene Akt/PKB (protein kinase B) has been demonstrated in certain neuro-endocrine tumours: Akt activates downstream proteins including mTOR and p70S6K, which...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000111501
更新日期:2008-01-01 00:00:00
abstract::Oxytocin receptors are regulated during parturition and lactation. Gonadal steroids are thought to be key players in this regulation. It is not well documented how oxytocin receptor gene expression is regulated in the CNS. In this study we analyzed potential estrogen effects on the oxytocin receptor mRNA levels in som...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000127160
更新日期:1997-01-01 00:00:00
abstract::We have investigated the effects of hyperprolactinemia, produced by pituitary isografts under the kidney capsule (16-20 days), on the LH releasing action and priming effect of LH-releasing hormone (LHRH) in normal and hypogonadal (hpg) female mice. The pituitary grafts increased the plasma prolactin concentrations abo...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124585
更新日期:1986-01-01 00:00:00
abstract::Several molecular forms related to the decapeptide LHRH were characterized and quantified in various brain structures of intact and castrated male and female rats. Distinct moieties were separated by high performance liquid chromatography (HPLC) and radioimmunoassayed against anti-LHRH antibodies of different specific...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126539
更新日期:1993-08-01 00:00:00
abstract::The effect of pinealectomy or immunization against melatonin (Mel) and N-acetylserotonin (NAS) on plasma prolactin (Prl) levels was studied in rats following pineal stimulation induced by blinding or exposure to short photoperiods (1 h light and 23 h darkness daily). Blinding alone or together with pinealectomy or imm...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000122650
更新日期:1977-01-01 00:00:00
abstract::Previous reports have shown that dopamine (DA) in the zona incerta (ZI) has a stimulatory effect on gonadotrophin release. We have now investigated the possibility that steroids exert their feedback effects on the release of luteinizing hormone (LH) via catecholamine systems in the ZI. Since the same steroid regimes a...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000125708
更新日期:1991-02-01 00:00:00
abstract:BACKGROUND/AIMS:Both prostaglandin E2 (PGE2) and estradiol stimulate fetal ACTH secretion and augment fetal ACTH responses to stress. We have reported that estradiol increases prostaglandin endoperoxide synthase-2 (PGHS-2), and we have proposed that there is a positive feedback relationship between estrogen and fetal h...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000109664
更新日期:2008-01-01 00:00:00
abstract::Studies were undertaken to investigate the nature of receptors involved in the prolactin-releasing action of histamine in male rats. The increase of plasma prolactin levels induced by third-ventricle injection of histamine was blocked by intraventricular injection of ranitidine, an H2-antagonist, but not by systemic a...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123495
更新日期:1983-06-01 00:00:00
abstract::The role of endogenous corticoids in fever responses caused by recombinant murine interleukin (IL)-1 beta and IL-6 was studied in adult male Wistar rats. Adrenalectomy diminished the development of fever after intracerebroventricular (icv) injection of these ILs and lowered body temperature. Intraperitoneal administra...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126682
更新日期:1994-04-01 00:00:00
abstract::Bromocriptine or other dopamine agonists are usually effective for the treatment of prolactin-secreting adenomas. Five to 18% of prolactinomas, however, do not respond to such therapy. We have shown previously that such resistance to bromocriptine correlates with reduced binding to the D2 receptor subtype of dopamine,...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126764
更新日期:1994-09-01 00:00:00
abstract::Hereditary cases of growth hormone (GH)-secreting tumors have been classified into three clinical entities: the multiple endocrine neoplasia type 1 (MEN1) syndrome, the Carney complex (CNC) and the isolated familial somatotropinomas (IFS). The genomic defects associated with MEN1 are all linked to various mutations of...
journal_title:Neuroendocrinology
pub_type: 杂志文章,评审
doi:10.1159/000095525
更新日期:2006-01-01 00:00:00
abstract::Thyroid hormones and nitric oxide/cyclic guanosine monophosphate (NO/cGMP) signaling play a significant role in the structural development of the cerebellum, respectively. In the present study, the possible contribution of neuronal NO synthase (NOS) and cGMP in the thyroid hormone-induced structural changes was invest...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000203644
更新日期:2009-01-01 00:00:00
abstract::Physiological brain aging is characterized by important biochemical and structural changes and by the unbalance among the different neurotransmitters and neuromodulators. The study of the circadian organization of neuroendocrine functions may be considered a clinically reliable tool to investigate the changes of the C...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126869
更新日期:1995-04-01 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::Insulin-deficient states are associated with an impaired function of the hypothalamic-pituitary-gonadal axis, but the mechanisms underlying hypothalamic alterations in experimental diabetes are still unknown. We investigated the effect of glucose concentrations, in the presence and absence of insulin, on LHRH release ...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126257
更新日期:1992-09-01 00:00:00
abstract::Immunoneutralization of endogenous gonadal steroids has recently been shown to modify pineal beta-adrenoceptor function in intact Merino ewes. In the current study, interactions between gonadal steroids and these receptors have been further investigated. beta-Adrenoceptor density and binding affinity both showed time-...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124225
更新日期:1985-12-01 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::Somatostatin receptors on lactotroph cells of the anterior pituitary are positively regulated by estradiol. In the present work, we investigated whether estradiol regulation of somatostatin receptors also occurred in the female rat brain. 125I-Tyr0-DTrp8-somatostatin (125I-SRIF: 780 Ci/mM) was used as a ligand. Female...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126234
更新日期:1992-08-01 00:00:00
abstract::The effects of intracerebroventricularly (i.c.v.) injected interleukin-1 beta (IL-1 beta: 1, 2.5, 10, and 25 ng) were studied on plasma growth hormone (GH) and prolactin (PRL) concentrations in freely moving rats chronically implanted with i.c.v. cannulas and intracardial catheters. Significant changes in PRL secretio...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126217
更新日期:1992-07-01 00:00:00