piperidines and Angelman-Syndrome

Angelman syndrome (AS) is a neurodevelopmental disorder caused by maternal deletions or mutations of the ubiquitin ligase E3A (UBE3A) allele and characterized by minimal verbal communication, seizures, and disorders of voluntary movement. Previous studies have suggested that abnormal dopamine neurotransmission may underlie some of these deficits, but no effective treatment currently exists for the core features of AS. A clinical trial of levodopa (L-DOPA) in AS is ongoing, although the underlying rationale for this treatment strategy has not yet been thoroughly examined in preclinical models. We found that AS model mice lacking maternal Ube3a (Ube3a(m-/p+) mice) exhibit behavioral deficits that correlated with abnormal dopamine signaling. These deficits were not due to loss of dopaminergic neurons or impaired dopamine synthesis. Unexpectedly, Ube3a(m-/p+) mice exhibited increased dopamine release in the mesolimbic pathway while also exhibiting a decrease in dopamine release in the nigrostriatal pathway, as measured with fast-scan cyclic voltammetry. These findings demonstrate the complex effects of UBE3A loss on dopamine signaling in subcortical motor pathways that may inform ongoing clinical trials of L-DOPA therapy in patients with AS.

Topics: Angelman Syndrome; Animals; Benzazepines; Cocaine; Disease Models, Animal; Dopamine; Dopamine D2 Receptor Antagonists; Dopamine Uptake Inhibitors; Dopaminergic Neurons; Electric Stimulation; Female; Indoles; Male; Mice; Mice, Inbred C57BL; Motor Activity; Piperidines; Raclopride; Receptors, Dopamine D1; Reward; Self Stimulation; Substantia Nigra; Synaptic Transmission; Ubiquitin-Protein Ligases; Ventral Tegmental Area

Angelman syndrome is a hereditary disease described by Angelman. The clinical features of Angelman syndrome are characterized by mental retardation, puppet-like ataxia, easily excitable personality, seizures, paroxysmal laughter, strabismus and macroglossia. A 4-year-old girl with Angelman syndrome underwent strabismus repair under general anesthesia. Anesthesia was slowly induced with sevoflurane in oxygen and maintained with air, oxygen, propofol and remifentanil. Tracheal intubation was performed after administration of rocuronium. During and after anesthesia, no adverse events regarding circulatory and respiratory systems occurred. However, this case demonstrates that it is necessary to pay attention to airway troubles including the difficulty of tracheal intubation, management of body temperature and chronotropic action or respiratory depression by anesthetic agents.

Topics: Anesthesia, General; Angelman Syndrome; Child, Preschool; Female; Humans; Intraoperative Care; Intubation, Intratracheal; Methyl Ethers; Monitoring, Intraoperative; Piperidines; Propofol; Remifentanil; Sevoflurane; Strabismus

Angelman's syndrome is an association of severe mental retardation with absence of language, ataxia, convulsions and hyperactive, joyful behaviour with frequent bouts of laughing. Genetic diagnosis is possible in about 80% of cases. No cardiovascular abnormalities have been described in this syndrome to date. The authors report the cases of three children with Angelman's syndrome who presented with severe malaise due to increased vagal tone. The age of onset of symptoms was between 20 months and 8 years. One of the children had malaises triggered by bouts of laughing. The diagnosis was confirmed in all three cases by the results of Holter 24 hour ECG recording and oculo-cardiac reflex. The treatment chosen was Diphemanil (Prantal) in the two patients under 2 years of age (after failure of a trial of betablockers in one case) and Disopyramide for the oldest child with excellent results in all cases. However, one child died suddenly at the age of 6, two years after stopping diphemanil. Based on these observations, the authors suggest that all malaises in patients with Angelman's syndrome should be investigated by Holter ECG and oculo-cardiac reflex (or tilt test). In view of the potential gravity of the syncopal attacks, long-term medical treatment seems to be justified.

Topics: Age of Onset; Angelman Syndrome; Child; Dipyridamole; Electrocardiography, Ambulatory; Female; Humans; Infant; Male; Parasympatholytics; Piperidines; Reflex, Oculocardiac; Vagus Nerve; Vasodilator Agents