摘要:

Abstract:A group of Vancouver health professionals, including the authors, have studied the use of oral melatonin in the treatment of chronic sleep disorders in children with disabilities since the Fall of 1991. This review article is based on the first 100 patients, half of whom were visually impaired or blind. Children with neurological, neuropsychiatric, and developmental disabilities are predisposed to chronic sleep‐wake cycle disturbances. Disorders such as blindness, deafblindness, mental retardation, autism, and central nervous system diseases, among others, diminish the ability of these individuals to perceive and interpret the multitude of cues for synchronizing their sleep with the environment. Melatonin, which benefitted slightly over 80% of our patients, appears to be a safe, inexpensive, and a very effective treatment of sleep‐wake cycle disorders. The oral dose of fast release melatonin taken at bed‐time ranged from 2.5 mg to 10 mg. Side effects or the development of tolerance have not been observed. Since the causes of sleep difficulties are extremely variable, not all children are candidates for treatment. For successful melatonin treatment, clinical experience is required, and the influences of other health problems and medications need to be considered. Further clinical and laboratory research in this field is imperative because melatonin treatment offers enormous health, emotional, social, and economic benefits to society, especially since multidisabled children with chronic sleep difficulties do not respond well to current therapeutic re

ISSN:0742-3098    

DOI:10.1111/j.1600-079X.1996.tb00286.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract:The role exerted by melatonin in human physiology has not been completely ascertained. Melatonin levels have been measured in different physiopathological conditions, but the effects induced by melatonin administration or withdrawal have been tested only recently. Some effects have been clearly documented. Melatonin has hypothermic properties, and its nocturnal secretion generates about 40% of the amplitude of the circadian body temperature rhythm. Melatonin has sleep inducing properties, and exerts important activities in the regulation of circadian rhythms. Melatonin is capable of phase shifting human circadian rhythms, of entraining free‐running circadian rhythms, and of antagonizing phase shifts induced by nighttime exposure to light. Its effect on human reproduction is not completely clear, but stimulatory effects on gonadotropin secretion have been reported in the follicular phase of the menstrual cycle. Direct actions on ovarian cells and spermatozoa have been also documented. Beside these, new important actions for melatonin may be proved. Melatonin may exert protective effects on the cardiovascular system, by reducing the risk of atherosclerosis and hypertension, and may influence immune responses. Finally, by acting as an antioxidant, melatonin could be important in slowing the processes of agein

ISSN:0742-3098    

DOI:10.1111/j.1600-079X.1996.tb00287.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract:Aleutian disease (AD) results from a persistent parvoviral infection that results in marked hypergammaglobulinemia and immune complex mediated lesions of the kidney, liver, lungs and, arteries. Melatonin protected both a wild type or demi strain and a demi/dark crossed strain of mink from AD. The biogenic amine also afforded protection against other non‐diagnosed diseases naturally found on mink farms when it was available from a subcutaneously‐placed reservoir. Some genetic strains of mink apparently differed in the resistance of mink to the virus and in the protective ability of melatonin. The demi strain was the most resistant followed by pastels, mahogany, darks, and those strains with the double recessive Aleutian gene. The protective action of melatonin appeared to result from melatonin's ability to scavenge free radicals, but it could also be due to the induction of antioxidant enzymes or to the modulation of immunity. Melatonin also protected mink against distem

ISSN:0742-3098    

DOI:10.1111/j.1600-079X.1996.tb00288.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

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 the day following light application. It appears that the animals were able to remember the light pulse if it was given 12 hr but not 9 hr after the lights were turned off. This memory could possibly be stored in the suprachiasmatic nucleus as reported recently in the

ISSN:0742-3098    

DOI:10.1111/j.1600-079X.1996.tb00289.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract:We investigated the relationship of urinary excretion rate of 6‐hydroxymelatonin sulfate (SM), the main metabolite of melatonin, with pubertal development and determined the day to day variability of SM excretion. Healthy subjects 4–31 years old completed one or multiple timed overnight urine collections. SM excretion rate per body size was significantly higher in 99 prepubertal subjects (35.5 ± 2.3 ng/h/kg and 0.97 ± 0.06 μ/hr/m) than in 86 pubertal subjects (18.1 ± 1.1 ng/hr/kg and 0.61 ± 0.03 μg/hr/m2) or in 29 adults (15.0 ± 1.5 ng/hr/kg and 0.59 ± 0.06 μg/hr/ m2); no significant difference was present in pubertal stages 2 to 5. Among the prepubertal children, SM excretion rate in mid childhood was significantly higher than in late childhood. The variability of SM and creatinine excretion examined in 52 children, adolescents and adults with three or four collections was defined as the mean of the 52 coefficients of variation for the multiple measures in each subject. The variability of total nocturnal SM (25.9 ± 2.6%) was similar to that of total creatinine (21.7 ± 2.3%) and neither was significantly correlated with the variability in start time or duration of urine collection. The results suggest that, relative to body size, melatonin secretion rate is higher in mid childhood, decreases during late childhood, and remains stable from pubertal stage 2 to adulthood. The decline in melatonin secretion rate occurs during the developmental phase of disinhibition of the gonadotropin releasing hormone pulse generator. Hence, we infer that melatonin may be a suppressive factor of puberty during childhood. The substantial individual variability observed for SM excretion calls for caution in using single urine collections in longitudinal studies or in studies of

ISSN:0742-3098    

DOI:10.1111/j.1600-079X.1996.tb00290.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract:The effects of exogenous melatonin on gonadal function and on the endogenous melatonin profiles of male and female Djungarian hamsters were investigated. Daily afternoon subcutaneous injections of melatonin (50 μ.g) in hamsters kept in long photoperiods (LD 16: 8) led to gonadal inhibition in all the treated females (n=13) but in only 2 of 13 males within the treatment period of 8 weeks (uteri: 244±11 mg in controls vs. 79±4 mg in treated hamsters,P<0.001; ovaries: 13.6±0.6 mg in controls vs. 7.9±0.7 mg in treated hamsters,P<0.001; testes: 1,021±54 mg in controls vs. 732±100 mg in treated hamsters,P0.05). These results indicate that there are some circumstances under which the gonadal responses of the reproductive organs of male and female Djungarian hamsters differ. Interestingly, pineal concentrations of melatonin were found to be significantly higher in males (P<0.01), possibly indicating a more robust endogenous supply with the hormone, whereas serum melatonin levels were not significantly different between males and females. However, the subcutaneous injection of melatonin (5, 25, and 125 μg) exerted no acute effect on the endogenous, circadian melatonin‐profile, independent of dos

ISSN:0742-3098    

DOI:10.1111/j.1600-079X.1996.tb00291.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract:Several experimental studies have shown that melatonin has an oncostatic action, either by stimulating host antitumor immune defenses or by directly inhibiting the growth of some cancer histotypes, including melanoma. Our previous clinical studies demonstrated that melatonin may induce stabilization of the disease in untreatable metastatic solid tumor patients, and these results have been confirmed by others, at least in patients with metastatic melanoma. On the contrary, at present there are no data related to the possible efficacy of melatonin as an adjuvant endocrine therapy. This study was performed to investigate the impact of melatonin therapy on the disease‐free survival (DFS) in melanoma patients surgically treated for regional node recurrence. The study included 30 node‐relapsed melanoma patients, who were randomized to receive no treatment or adjuvant therapy of melatonin (20 mg/day orally in the evening) every day until disease progression. After a median follow‐up of 31 months, the percent of DFS was significantly higher in melatonin‐treated individuals than in controls. The DFS curve was also significantly longer in melatonin group than in controls. No melatonin‐related toxicity was observed. This preliminary study suggests that an adjuvant endocrine therapy with melatonin may be effective in preventing disease progression in node‐relapsed melano

ISSN:0742-3098    

DOI:10.1111/j.1600-079X.1996.tb00292.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract:6‐Sulphatoxymelatonin (aMT6S) excretion was examined in the urine of rhythmic and arrhythmic blind subterranean mole rats (Spalax ehrenbergi) to test the correlation between melatonin secretion (as represented by aMT6S) and variability in circadian locomotor activity. Activity pattern was tested in four males, first for a week under short photoperiod [light: dark (LD) 10: 14], followed by 10 days in constant darkness (DD). After several months the experiment was repeated under long photoperiod (LD 14: 10), followed by DD conditions. Under LD conditions all animals exhibited aMT6S excretion during the dark phase, with a decline just before the onset of light. No correlation was found between activity pattern and melatonin secretion. The animal with the highest melatonin secretion both under LD and DD had an arrhythmic locomotor pattern. The results suggest that in mole rats melatonin secretion and circadian locomotor activity are controlled by two different mechanisms. There were large differences in the aMT6S levels among individuals, suggesting the importance of duration of melatonin secretion over amplitude for gonadal development and thermoregulatory changes. During summer, i.e., before the breeding season, the animals keep a more stable aMT6S secretion than in winter, and the amplitude of secretion is higher under DD vs. LD condition

ISSN:0742-3098    

DOI:10.1111/j.1600-079X.1996.tb00293.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY

摘要:

Abstract:Melatonin concentrations were determined in serum and 10 segments of the gastrointestinal tract (GIT) of 48 pigs (100 kg weight). The animals were fasted for 30 hr and then sacrificed 0, 1,2, 5, 10, and 20 hr after refeeding. Peak amount of gastric digesta (2,428 g) and ileum digesta (850 g) were observed 1 hr and 5 hr, after refeeding, respectively. Conversely, colon content reached a minimal weight (726 g) at 2 hr after refeeding. Serum levels of melatonin increased from 3.4 pg/ml to 15.5 pg/ ml (peak 5 hr after refeeding). Melatonin levels in GIT tissues before refeeding varied from 23.8 pg/g (stomach‐fundus) to 62.1 pg/g (rectum). Increasingly higher levels of melatonin were detected in the distal segments of the GIT. Higher melatonin levels after refeeding were observed in most GIT tissues except the rectum. In most tissues, peak melatonin values were detected 5 hr after refeeding. A significant change in weight of digesta across time (P<0.05) was detected in the stomach, ileum, and cecum. Similar changes in melatonin levels across time were found in most tissues except the esophagus, stomach (cardia and pylorus), and rectum. Adjacent GIT tissues exhibited similar (P<0.05) melatonin levels. The GIT melatonin levels correlated best with the variation of digesta weight in the ileum. In addition, the increase of serum melatonin levels correlated best with the increase of GIT melatonin levels in the distal part of the GIT. Our results suggest that melatonin produced in the ileum, cecum, and colon may contribute significantly to the short‐term increase of serum melatonin levels observed after refeed

ISSN:0742-3098    

DOI:10.1111/j.1600-079X.1996.tb00294.x

出版商:Blackwell Publishing Ltd    

年代:1996

数据来源: WILEY