Effects of 5-HT7 receptors on circadian rhythm of mice anesthetized with isoflurane

The role of the serotonin 7 receptor (5-HT₇ receptor) subtype in a number of domains has been widely recognized, but its role in the regulation of changes of the circadian rhythm after anesthesia is still unclear. We used intraperitoneal injection of 5-HT₇ receptor agonist LP-211 or antagonist SB-269970 in mice to influence the level of 5-HT₇ receptor protein in the SCN and to observe the role of this receptor on circadian rhythm changes after isoflurane anesthesia. Our results show the appropriate dose of SB-269970 significantly alleviated the circadian rhythm disorder induced by isoflurane anesthesia, while LP-211 significantly aggravated it after anesthesia, which is different from the phase shift that can be caused by the administration of LP-211 before anesthesia. These findings may indicate the 5-HT₇ receptor plays a complex role in the regulation of circadian rhythm after anesthesia. Our findings may provide some positive significance for alleviating circadian rhythm disorder in patients after anesthesia and ultimately promoting rapid postoperative recovery.

Serotonin Type 6 and 7 Receptors as a Novel Therapeutic Target for the Treatment of Schizophrenia

Schizophrenia is a serious disease of the central nervous system that affects a person's ability to think, feel and behave clearly. Even though the pathophysiological hypothesis of the disease is not clearly understood, dysfunction of dopamine, glutamate, serotonin and other neurotransmitters is widely believed to be involved. Serotonin within the synaptic vesicles functions as neurotransmitter and neurohormone in regulation of emotion, learning, memory, hormone release, cognition and motor function. Dysfunction of normal brain activity of serotonin is associated with schizophrenia. The role of serotonin 6 and 7 receptors in schizophrenia, interaction with neurotransmitters and the effect of drugs on those receptors in schizophrenia are the goal of this review. The aim of this review was to provide information for researchers and other scholars to identify the possible intervention points in the management of schizophrenia. The serotonin 6 and 7 receptors are associated with schizophrenia via modulating cyclic adenosine monophosphate, regulation of Fyn kinase and induction of structural plasticity. The above modulatory effects affect cholinergic, dopaminergic, glutamatergic, adrenergic and GABAergic systems. Recently, diverse numbers of selective agonist and antagonist ligands were developed for both receptors. SGS-518, ABT-354, Lu AE58054, SB-742,457, S-518, AVN-211, AVN-322, SYN-114 and SYN-120 are serotonin 6 receptor antagonists and aripiprazole-controlled release serotonin 7 receptor agonists under clinical trial for schizophrenia. Thus, research on novel drugs that act on serotonin 6 and 7 receptors likely facilitates the intervention into schizophrenia patients seeking better quality of life in the future.