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Plasma hormones (arginine vasotocin, prolactin, aldosterone, and corticosterone) in relation to hydration state, NaCl intake, and egg laying in fowls.

This review surveys our latest research dealing with the involvement of arginine vasotocin (AVT), the avian antidiuretic hormone, and other hormones in the regulation of water and salt balance in fowl. We examined the effect of dehydration, salt loading, high- and low-salt diets, and oviposition on plasma hormone levels and analyzed them in light of our knowledge of avian osmoregulatory responses to changes in water and salt balance. Gradual dehydration and hyperosmotic loading in domestic fowl revealed consistent differences in the AVT response between groups adapted to low- and high-NaCl die

Prolactin response to the dopamine antagonists sulpiride and domperidone. Further evidence for pituitary dopamine deficiency in hyperprolactinemic disorders of different etiology.

The PRL response to the dopamine antagonists sulpiride (100 mg i.m.) or domperidone (2 or 8 mg i.v.) was evaluated in healthy controls and in 148 patients with different hyperprolactinemic disorders (50 with idiopathic hyperprolactinemia, 58 with microprolactinoma, 19 with macroprolactinoma, 2 with empty sella, 8 with acromegaly, 7 with organic lesions of the hypothalamus, and 4 with idiopathic hypopituitarism of presumed hypothalamic origin). Mean PRL response to both drugs was significantly lower in all groups of patients than in controls, and significantly higher in subjects with idiopathic…

Effects of growth hormone, prolactin, and placental lactogen on insulin content and release, and deoxyribonucleic acid synthesis in cultured pancreatic islets.

The direct effects of human GH (hGH), ovine pituitary PRL (oPRL), and human chorionic somatomammotropin [placental lactogen (hPL)] on the endocrine pancreas were studied in isolated pancreatic islets maintained in tissue culture. Islets of Langerhans were isolated by collagenase treatment of pancreatic tissue obtained from adult NMRI mice and adult or newborn Wistar rats. The islets were maintained for up to 3 weeks in petri dishes containing tissue culture medium RPMI 1640 supplemented with newborn calf serum or normal human serum. The release of insulin during culture and the islet content o

Direct effects of sex steroids on prolactin release at the anterior pituitary level: interactions with dopamine, thyrotropin-releasing hormone, and isobutylmethylxanthine.

When present alone for 4 or 8 days, 5 alpha-dihydrotestosterone (DHT) or the pure progestin R5020 (17,21-dimethyl-19-nor-4,9-pregnadiene-3,20-dione) inhibits spontaneous PRL release by 33--50% in rat anterior pituitary cells in primary culture. This inhibitory effect of DHT and R5020 can only be partially reversed by 17 beta-estradiol (E alpha). DHT and R5020 inhibit spontaneous PRL release in E2-primed cells at ED50 values of 0.5 and 3 nM, respectively. While E2 diminishes by 30--60% the maximal inhibitory effect of dopamine on PRL release and increases by 10-fold the ED50 value of dopamine a

Dissociation in the regulation of luteinizing hormone and follicle-stimulating hormone in a hyperprolactinaemic rat model: interrelationships between gonadotrophin and prolactin control.

Male and female Wistar rats were made hyperprolactinaemic by grafting two pituitary glands of litter-mate donors under the kidney capsule at 30 days of age. Other animals were sham-operated at the same age to serve as controls. Plasma levels of prolactin, LH and FSH were measured by double-antibody radioimmunoassay. Basal preoperative prolactin levels of approximately 10 ng/ml increased after the transplantation in both male and female rats, reaching values of approximately 180 ng/ml. Levels of LH were significantly reduced in these hyperprolactinaemic rats, whereas an increase in FSH values w…

Studies on rat pituitary homografts. II. Effects of thyrotropin-releasing hormone on in vitro biosynthesis and release of growth hormone and prolactin.

A study was made of the effect of TRH, administered in vivo by iv infusion or added in vitro to the incubation fluid, on tissue fragments prepared from rat normotopic and ectopic pituitaries. The latter were 30-day-old pituitary grafts transplanted under the kidney capsule in hypophysectomized animals. No detectable effect of TRH was found with normotopic glands. In contrast, the neurohormone produced a large increase in GH and PRL biosynthesis in the grafts, as revealed by the rise in hormone content as well as increased incorporation of L-[3H]leucine into the two hormones. These effects of T

Уровни гингивальной креветочной жидкости пролактина у пациентов, страдающих периодонтитом, с контролируемым или неконтролируемым типом 2 диабет. Контролируемое клиническое испытание.

В ходе этого исследования были исследованы уровни гингивальной кревикулярной жидкости (ГХФ) гормона пролактина (ПРЛ) на этапе III периодонтит (П) пациентов с типом 2 сахарный диабет (T2DM) до и 3 через несколько месяцев после нехирургической периодической терапии (НППТ). В этом деле под контролем суда, 80 Темы были разделены на 4 группы: группа I: здоровый контроль; группа II: системно здоровый этап III P пациентов; группа III: этап III P пациентов с контролируемым Т2ДМ; группа IV: этап III P пациентов с неконтролируемым Т2ДМ. Все пациенты П получили NSPT. Three Спустя несколько месяцев после

Совпадение в аннотации оригинала
This study investigated gingival crevicular fluid (GCF) levels of prolactin hormone (PRL) in stage III periodontitis (P) patients with type 2 diabetes mellitus (T2DM) before and 3 months after non-surgical periodontal treatment (NSPT). In this case-controlled trial, 80 subjects were divided into 4 groups: group I: healthy control; Group II: systemically heal…

Prolactin levels increased by physical exercise correlate with platelet monoamine oxidase activity: Evidence linking platelet MAO with serotonin release capacity.

OBJECTIVE: Lower platelet monoamine oxidase (MAO) activity has consistently been associated with excessive risk-taking and general psychiatric vulnerability. How this peripheral measure can represent presumably centrally regulated complex behaviours is not clear but platelet MAO activity has been suggested to reflect the capacity of serotonin release in the brain. Secretion of prolactin is in part under serotonergic control and indicates serotonin release capacity. METHODS: We have assessed release of prolactin and other exercise-induced hormones in response to strenuous physical exercise in …

Letrozole Decreased Testosterone-Induced Cell Proliferation and Prolactin Secretion also Increased Apoptosis in MMQ and GH3 Rat Prolactinoma Cell Lines.

Aromatase enzyme plays an essential role in estrogen-induced tumorigenesis. It is expressed in the normal pituitary and more significantly in prolactinoma tissues. The aim of this study was to investigate the effects of an aromatase inhibitor, letrozole, on MMQ and GH3 rat prolactinoma cell lines and evaluate the possible mechanism of action. MMQ and GH3 cells were characterized with demonstrating aromatase enzyme and estrogen receptor alpha expression by PCR and immunofluorescence staining. After dose optimization for testosterone (T) and letrozole (L), four groups were established: only the …

Unique features of pregnancy-related meningiomas: lessons learned from 148 reported cases and theoretical implications of a prolactin modulated pathogenesis.

Meningiomas are some of the most frequently encountered adult intracranial tumors. Dramatic flare ups in size may occasionally be observed d … ated to hormonal influences of the pituitary gland, and we discuss that this may be due to elevated prolactin levels. We encourage further research to test this exciting new theory.

PAK1 regulates breast cancer cell invasion through secretion of matrix metalloproteinases in response to prolactin and three-dimensional collagen IV.

p21-Activated serine-threonine kinase (PAK1) is implicated in breast cancer. We have shown previously that PAK1 is tyrosyl phosphorylated by prolactin (PRL)-activated Janus tyrosine kinase (JAK2). Although a role for both PRL and PAK1 in breast cancer is widely acknowledged, the mechanism remains poorly understood. In the present study, PRL-activated PAK1 stimulates the invasion of TMX2-28 human breast cancer cells through Matrigel. Three-dimensional (3D) collagen IV stimulates the secretion of the matrix proteases, metalloproteinase (MMP)-1 and -3 that is further enhanced by the PRL-dependent…

Estrogen inhibits D2S receptor-regulated Gi3 and Gs protein interactions to stimulate prolactin production and cell proliferation in lactotropic cells.

The neurotransmitter dopamine (DA) is known to inhibit prolactin (PRL) secretion and the proliferation of lactotropes in the pituitary gland. Dopamine-2 (D2) receptor short (D2S) isoform is expressed in a reduced level while the D2 receptor long (D2L) isoform is expressed in an elevated level during estradiol (E(2))-induced PRL production and cell proliferation in lactotropes. To evaluate the role of these D2 receptor isoforms in E(2)-regulated lactotropic cell function, we compared E(2) effects on the level of PRL, cell proliferation, and G proteins in enriched lactotropes and lactotrope-deri…

Structurally conserved C-RFa revealed prolactin releasing activity in vitro and gene expression changes in pituitary of seasonally acclimatized carp.

Here we show the cloning and characterization of a novel homolog of prepro C-RFa cDNA from Cyprinus carpio. The deduced preprohormone precursor of 115 amino acids leads to a mature bioactive peptide of 20 amino acids with identical sequence to other teleost C-RFa. Modeling of the mature C-RFa peptide highlighted significant similarity to homologous human PrRP20, specifically the conserved amphipathic system defined by the C-terminal alpha-helix. Clearly, the synthetic C-RFa peptide stimulated prolactin release from primary cultured fish pituitary cells. For the first time, significant variatio…

Short-term prolactin administration causes expressible galactorrhea but does not affect bone turnover: pilot data for a new lactation agent.

BACKGROUND: Medications used to augment lactation increase prolactin secretion but can have intolerable side effects. We examined the biological activity of recombinant human prolactin (r-hPRL) as preliminary data for its use to augment lactation. METHODS: Healthy, non-postpartum women (n = 21) with regular menstrual cycles underwent a seven day randomized, double-blind, placebo-controlled trial of r-hPRL. Expressible galactorrhea, markers of bone turnover, calcium homeostasis and gonadal function were measured and side effects recorded. RESULTS: Prolactin levels increased during r-hPRL admi…

[A case of multiple endocrine neoplasia type I with primary hyperparathyroidism, prolactin secreting pituitary microadenoma and gastrin secreting duodenal carcinoid].

A case of MEN type I in a 64-year-old man is reported. He had undergone partial duodenectomy because of gastric ulcer and multiple duodenal polyps (gastrin secreting carcinoid). Blood examination revealed hypercalcemia, hyperPTHemia, and hyperprolactinemia. Neck US and CT showed enlargement of 4 parathyroid glands. Brain MRI revealed the microadenoma in left pituitary gland. Total parathyroidectomy with auto-transplantation in the left forearm were performed. Histological examination showed the hyperplasia of the parathyroid. Three and a half year after parathyroidectomy, there was no evidence…

Effect of posterior pituitary denervation (PPD) on prolactin (PRL) and alpha-melanocyte-stimulating hormone (alpha-MSH) secretion of lactating rats.

Previous data have clearly suggested that the posterior pituitary (PP), consisting of neural lobe (NL) and intermediate lobe (IL), has a role in the control of anterior pituitary PRL secretion. However, basic aspects of this regulatory mechanism like (1), the role of an intact hypothalamic innervation of the PP as well as (2) the site of production of previously found PRL releasing substance(s) have not yet been characterized. Denervation of the PP (PPD) is an effective method for having a selective lesion of the innervation of PP, indeed, PPD results in a disappearance of neurosecretory mater

Circulating levels of growth hormone, insulin-like growth factor-I and prolactin in normal, growth retarded and anencephalic human fetuses.

We measured growth hormone (GH), insulin-like growth factor-I (IGF-I), and both total and glycosylated prolactin (PRL) levels in 131 blood samples obtained by cordocentesis in normal and abnormal fetuses from 19 to 40 weeks of gestation. In normal fetuses, IGF-I and PRL levels showed a positive correlation and GH a negative correlation with gestational age. A negative relation between GH and IGF-I levels was observed, while PRL did not show any correlation with both GH and IGF-I concentrations. IGF-I increased from 5.6 +/- 3 (at 19-22 weeks) to 10.7 +/- 5 nmol/l at term; GH decreased from 31 +…

Prolactin and bromocriptine induced changes in liver, adipose tissue and blood lipids of mature male bonnet monkeys, Macaca radiata (Geoffroy).

Effects of prolactin and bromocriptine on neutral and phospholipids of liver, adipose tissue and serum were studied in mature male bonnet monkeys. Hyperprolactinemia (ovine prolactin, 250 micrograms/kg body weight/day, i.p. for 30 days) elevated hepatic total lipids and phospholipids and decreased total and free cholesterol. While triacyl glycerol accumulated, mono-and diacyl glycerols diminished in liver and adipose tissues of prolactin treated monkeys. Concentrations of all phospholipid fractions, except sphingomyelin and cardiolipin in adipose tissue accrued in both tissues. Serum triacylgl…