Melatonin is a pleiotropic signalling molecule that regulates several physiological functions, and synchronises biological rhythms. Recent evidences are beginning to reveal that a dysregulation of endogenous melatonin...Melatonin is a pleiotropic signalling molecule that regulates several physiological functions, and synchronises biological rhythms. Recent evidences are beginning to reveal that a dysregulation of endogenous melatonin rhythm or action may play a larger role in the aetiology and behavioural expression of drug addiction, than was previously considered. Also, the findings from a number of animal studies suggest that exogenous melatonin supplementation and therapeutic manipulation of melatonin/melatonin receptor interactions may be beneficial in the management of behavioural manifestations of drug addiction. However, repeated exogenous melatonin administration may cause a disruption of its endogenous rhythm and be associated with potential drawbacks that might limit its usefulness. In this review, we examine the roles of melatonin and its receptors in addictive behaviours; discussing how our understanding of melatonin's modulatory effects on the brain rewards system and crucial neurotransmitters such as dopamine has evolved over the years. Possible indications(s) for melatonergic agents in addiction management, and how manipulations of the endogenous melatonin system may be of benefit are also discussed. Finally, the potential impediments to application of melatonin in the management of addictive behaviours are considered.展开更多
The suprachiasmatic nucleus(SCN), an endogenous clock in the brain of the mammals, regulates the physiological and behavioral activities according to the natural 24 h light-darkness cycle. Animals can also entrain the...The suprachiasmatic nucleus(SCN), an endogenous clock in the brain of the mammals, regulates the physiological and behavioral activities according to the natural 24 h light-darkness cycle. Animals can also entrain themselves to non 24 h light-darkness cycles. The range of the periods which the animal can entrain to is called entrainment range. Previous studies have found that the entrainment range depends on the coupling strength and the sensitive strength to the light for the SCN neurons. However, the effect of the interplay between these two strengths on the entrainment range has not been examined. In the present study, we examine the effect of the ratio of the sensitive strength to the coupling strength on the entrainment range. We find that there is a parabolic-like relationship between the entrainment range and the ratio, and the largest entrainment range is obtained with a suitable ratio. Interestingly,the value of this suitable ratio is related to the comparison in the intrinsic amplitudes between the light information sensitive neurons and the light information insensitive neurons. Our finding will shed light on the interplay between the sensitive strength to the light information and the coupling strength, and the understanding for the diversity of the entrainment range among various species.展开更多
文摘Melatonin is a pleiotropic signalling molecule that regulates several physiological functions, and synchronises biological rhythms. Recent evidences are beginning to reveal that a dysregulation of endogenous melatonin rhythm or action may play a larger role in the aetiology and behavioural expression of drug addiction, than was previously considered. Also, the findings from a number of animal studies suggest that exogenous melatonin supplementation and therapeutic manipulation of melatonin/melatonin receptor interactions may be beneficial in the management of behavioural manifestations of drug addiction. However, repeated exogenous melatonin administration may cause a disruption of its endogenous rhythm and be associated with potential drawbacks that might limit its usefulness. In this review, we examine the roles of melatonin and its receptors in addictive behaviours; discussing how our understanding of melatonin's modulatory effects on the brain rewards system and crucial neurotransmitters such as dopamine has evolved over the years. Possible indications(s) for melatonergic agents in addiction management, and how manipulations of the endogenous melatonin system may be of benefit are also discussed. Finally, the potential impediments to application of melatonin in the management of addictive behaviours are considered.
基金Supported by the National Natural Science Foundation of China under Grants Nos.11875042,11505114 and No.10975099the National Natural Science Key Foundation of China No.61433015the Program for Professor of Special Appointment(Orientational Scholar)at Shanghai Institutions of Higher Learning under Grants Nos.QD2015016 and D-USST02
文摘The suprachiasmatic nucleus(SCN), an endogenous clock in the brain of the mammals, regulates the physiological and behavioral activities according to the natural 24 h light-darkness cycle. Animals can also entrain themselves to non 24 h light-darkness cycles. The range of the periods which the animal can entrain to is called entrainment range. Previous studies have found that the entrainment range depends on the coupling strength and the sensitive strength to the light for the SCN neurons. However, the effect of the interplay between these two strengths on the entrainment range has not been examined. In the present study, we examine the effect of the ratio of the sensitive strength to the coupling strength on the entrainment range. We find that there is a parabolic-like relationship between the entrainment range and the ratio, and the largest entrainment range is obtained with a suitable ratio. Interestingly,the value of this suitable ratio is related to the comparison in the intrinsic amplitudes between the light information sensitive neurons and the light information insensitive neurons. Our finding will shed light on the interplay between the sensitive strength to the light information and the coupling strength, and the understanding for the diversity of the entrainment range among various species.
