Abstract:
:The effect of melatonin (0.1 microM) on freshly isolated islets from adult rats was investigated. Melatonin caused a marked decrease of insulin secretion by islets in response to glucose. The mechanism involved was then examined. Melatonin did not interfere with glucose metabolism as indicated by the measurement of glucose oxidation. However, the content of the protein kinase A (PKA) catalytic alpha-subunit was significantly decreased in islets exposed to melatonin for 1 hr in the presence of 8.3 mM glucose, whereas that of the protein kinase C (PKC) alpha-subunit remained unchanged. Melatonin also inhibited forskolin-induced insulin secretion, a well known activator of adenylate cyclase (AC) activity. This may explain the low content of insulin found in islets incubated in the presence of melatonin for 3 hr. In fact, 3',5' -cyclic adenosine monophosphate (cAMP), a product of AC activity, stimulates insulin synthesis. These findings led us to postulate that a down-regulation of the PKA signaling pathway may be the mechanism involved in the melatonin inhibition of the process of glucose-induced insulin secretion.
journal_name
J Pineal Resjournal_title
Journal of pineal researchauthors
Picinato MC,Haber EP,Cipolla-Neto J,Curi R,de Oliveira Carvalho CR,Carpinelli ARdoi
10.1034/j.1600-079x.2002.02903.xsubject
Has Abstractpub_date
2002-10-01 00:00:00pages
156-60issue
3eissn
0742-3098issn
1600-079Xpii
2o903journal_volume
33pub_type
杂志文章abstract::Female Syrian hamsters were kept in a light (14:10 h light:dark cycle, lights on 0600 h)- and temperature (22 or 30 degrees C)-controlled room; some groups were treated with an afternoon s.c. injection of melatonin (6.25, 12.5, or 25 micrograms/day) for 11 or 14 weeks. The melatonin-induced suppression of the reproduc...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1988.tb00656.x
更新日期:1988-01-01 00:00:00
abstract::Melatonin, a neurohormone that binds to two G protein-coupled receptors MT1 and MT2, is involved in pain regulation, but the distinct role of each receptor has yet to be defined. We characterized the nociceptive responses of mice with genetic inactivation of melatonin MT1 (MT1-/- ), or MT2 (MT2-/- ), or both MT1 /MT2 ...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/jpi.12671
更新日期:2020-10-01 00:00:00
abstract::Although there is an increasing evidence that the pineal gland may play a role in human malignancy, the studies on melatonin concentrations in different types of malignant tumors brought about controversial results. However, changes in melatonin concentrations have been observed in some types of human malignant tumors...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2005.00221.x
更新日期:2005-08-01 00:00:00
abstract::Excessive production of nitric oxide (NO) may play a detrimental role in the process of hypoxia-related neuropathology. This study explored whether treatment with melatonin would attenuate the neuropathological changes in the vagal ganglia following a severe hypoxic insult. Thirty minutes prior to hypoxia treatment, y...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1034/j.1600-079x.2002.1816.x
更新日期:2002-03-01 00:00:00
abstract::The frequency of mitoses of adrenaline (A) cells and noradrenaline (N) cells in the adrenal medulla of nonoperated (NO), sham-operated (SPX), and pinealectomized (PX) male, 53-day-old Holtzman rats (n = 133) was investigated by means of light microscopy. Animals were killed at eight time points during a standardized 2...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1990.tb00803.x
更新日期:1990-01-01 00:00:00
abstract::Melatonin was tested in an ongoing attempt to find the endogenous antagonists of quinolinic acid, an endogenous convulsant. Among a great number of metabolites that have been tried before, only a few were found (cerulein and quinaldic acid in mice and kynurenic acid in rats). In SHR (bred from Swiss) male mice, intrac...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1998.tb00535.x
更新日期:1998-05-01 00:00:00
abstract::Melatonin, a potent antioxidant, has shown to be beneficial in murine Venezuelan equine encephalomyelitis (VEE) virus infection. In addition, melatonin can induces the production of interleukin-1 beta (IL-1beta), a cytokine capable of inducing increased expression of inducible nitric oxide synthase; the activity of th...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2006.00381.x
更新日期:2007-03-01 00:00:00
abstract::We previously reported that pharmacological melatonin administration to type 2 diabetic rats reduces hyperinsulinemia and improves the altered fatty-acid metabolism. To determine whether melatonin deficiency exacerbates diabetes-associated conditions, we investigated the effect of pinealectomy (i.e. melatonin-deficien...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1034/j.1600-079x.2003.00083.x
更新日期:2003-11-01 00:00:00
abstract::The effect of daily injection of the pineal hormone melatonin and naltrexone, an opioid antagonist, on the circadian rhythm and the level of immune parameters (plaque forming cell [PFC] number, serum agglutinin titer, lymphoid gland weight, total white blood cells (WBC) and their fraction number, and serum lysozyme [L...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1992.tb00022.x
更新日期:1992-01-01 00:00:00
abstract::Possible role of melatonin in the germination of negatively photoblastic and thermosensitive seeds of Phacelia tanacetifolia Benth was studied. Final germination percentage (FGP) was determined in the presence or absence of light at various temperatures, ranging from 0 to 40°C. The highest FGP was determined as 48.7% ...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2011.00947.x
更新日期:2012-04-01 00:00:00
abstract::Experiments were conducted to determine whether daily melatonin injections could influence reentrainment of circadian locomotor activity rhythms in male Long-Evans rats after phase shifts of the light dark (LD) cycle. When exposed to a 5-h advance of the LD cycle, six out of 15 rats injected daily with melatonin at th...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1988.tb00782.x
更新日期:1988-01-01 00:00:00
abstract::The circadian system comprises several peripheral oscillators and a central rhythm generator that, in mammals, is located in the suprachiasmatic nucleus of the hypothalamus. Expression of clock genes is a characteristic feature of the central rhythm generator and the peripheral oscillators. With regard to the rhythmic...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2005.00279.x
更新日期:2006-01-01 00:00:00
abstract::The milk-ejecting response of lactating mouse mammary gland tissue to ovine pineal extracts indicated the presence of a neurohormone-like bioactivity in this tissue. After successive fractionation on gel permeation chromatography and reversed-phase liquid chromatography (HPLC) in conjunction with radioimmunoassays (RI...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1988.tb00800.x
更新日期:1988-01-01 00:00:00
abstract::The pineal hormone melatonin, due to its lipophilic nature, has access to every cell and every part of a cell in the body, suggesting that it could exert effects on blood immune cells. The regulation of the activation of monocytes may be important in a number of diseases, especially pathophysiological conditions assoc...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1999.tb00566.x
更新日期:1999-01-01 00:00:00
abstract::Rat pineal hydroxyindole-O-methyltransferase (HIOMT; EC 2.1.1.4) was purified by affinity chromatography using an S-adenosyl-L-homocysteine agarose column. This single-step procedure, which is rapid, simple, and applicable to small quantities of tissue, gave a large enrichment of a protein (Mr approximately 38,000) id...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1986.tb00761.x
更新日期:1986-01-01 00:00:00
abstract::In the current study, a fundamental question, that is, the mechanisms related to the beneficial effects of melatonin on mammalian embryonic development, was addressed. To examine the potential beneficial effects of melatonin on bovine embryonic development, different concentrations of melatonin (10(-11), 10(-9), 10(-7...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/jpi.12126
更新日期:2014-04-01 00:00:00
abstract::This study examined the factors that may be involved in altering the function of pineal gland in hypoxic conditions. Adult Wistar rats were subjected to hypoxia and the pineal gland was examined for the mRNA and protein expression of hypoxia-inducible factor-1alpha (HIF-1alpha), vascular endothelial growth factor (VEG...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2007.00424.x
更新日期:2007-04-01 00:00:00
abstract::Previous data have demonstrated that a single 1-hr light pulse at night affects the secretion of melatonin in the ram if it was given at the appropriate time. This paper reports the effect on melatonin secretion of a 1-hr light pulse given at two different times at night to two groups of rams kept in constant darkness...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1996.tb00289.x
更新日期:1996-11-01 00:00:00
abstract::We evaluated the antioxidant property of melatonin as it relates to the vasospastic effect of hydrogen peroxide (H2O2) on the human umbilical artery. Helical sections of umbilical arteries were obtained from healthy pregnant women who were delivered between weeks 37 and 39 of gestation. Changes in maximal potassium ch...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1997.tb00318.x
更新日期:1997-04-01 00:00:00
abstract::The influence of the pineal gland on the histopathologic changes induced in mammary glands by 7, 12-dimethylbenz(a)-anthracene (DMBA) has been studied. To achieve the maximum expression of pineal action in animals, 28-day-old female Sprague-Dawley rats were subjected to one of the following treatments: blindness + olf...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1989.tb00418.x
更新日期:1989-01-01 00:00:00
abstract::We evaluated the feasibility of using morning urine samples in epidemiological studies aimed at clarifying the relationship between nocturnal melatonin levels and breast cancer risk. Initially, a laboratory-based study of 29 women (40- 70 yr old) was performed to examine the correlation between plasma melatonin levels...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1034/j.1600-079x.2000.280106.x
更新日期:2000-01-01 00:00:00
abstract::The activity of N-acetyltransferase (NAT) and the content of melatonin (MEL) in the rat pineal have been shown to be sensitive to several types of stressors. This study was designed to assess the role of the adrenals in mediating the effect of one such stressor, insulin-induced hypoglycemia, on pineal synthetic activi...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1987.tb00879.x
更新日期:1987-01-01 00:00:00
abstract::Melatonin, the major secretory product of the pineal gland, is in focus of many research areas because of its ability to scavenge free oxygen radicals and thereby protect cells and tissues from radical damage. Some studies suggest melatonin may be a possible therapeutic agent with potential clinical applications again...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1034/j.1600-079x.2002.01846.x
更新日期:2002-08-01 00:00:00
abstract::Lethal oxidative stress was investigated in the dinoflagellate Gonyaulax polyedra by measuring the dying-peak of bioluminescence during circadian phases of low physiological light emission, low bioluminescence capacity, and low sensitivity to stimulatory agents. Measurements were carried out in constant darkness after...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079x.1997.tb00353.x
更新日期:1997-11-01 00:00:00
abstract::The protective role of exogenous melatonin on U-induced nephrotoxicity was investigated in rats. Animals were given single doses of uranyl acetate dihydrate (UAD) at 5 mg/kg (subcutaneous), melatonin at 10 or 20 mg/kg (intraperitoneal), and UAD (5 mg/kg) plus melatonin (10 or 20 mg/kg), or vehicle (control group). In ...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2007.00447.x
更新日期:2007-08-01 00:00:00
abstract::Melatonin, the main secretory product of the pineal gland, has been shown to be potentially effective in prevention of numerous types of neurodegenerative disorders in which free radical processes are involved. Homocysteine (Hcy), an independent risk factor for atherosclerosis, undergoes auto-oxidation and generates r...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1034/j.1600-079x.2003.02939.x
更新日期:2003-01-01 00:00:00
abstract::In a recent study melatonin (N-acetyl-5-methoxytryptamine), a well-investigated animal molecule but minimally studied in plants, was seen to have a physiological role as growth-promoting molecule in lupin hypocotyls. In the present study, the role of melatonin as a growth promoter is extended to coleoptiles of canary ...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2005.00226.x
更新日期:2005-09-01 00:00:00
abstract::The association of seasonal changes in health and disease has been known for centuries. The prevalence of psychopathological symptoms with seasonal fluctuations and the use of melatonin as a biological marker of circadian and circannual rhythms is well documented. The aim of this work was to study the variability of m...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2006.00365.x
更新日期:2006-10-01 00:00:00
abstract::Atherosclerosis (AS) is an inflammatory disease linked to endothelial dysfunction. Melatonin is reported to possess substantial anti-inflammatory properties, which has proven to be effective in AS. Emerging literature suggests that pyroptosis plays a critical role during AS progression. However, whether pyroptosis con...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/jpi.12449
更新日期:2018-03-01 00:00:00
abstract::Melatonin, a molecule produced in the pineal gland and retina of vertebrates, plays a major role in day-night circadian rhythms and other physiological processes, including the immune responses. Because little is known in this respect in fish, we have evaluated the in vivo role of melatonin in the main innate immune a...
journal_title:Journal of pineal research
pub_type: 杂志文章
doi:10.1111/j.1600-079X.2008.00557.x
更新日期:2008-08-01 00:00:00