Autism neuropeptides

Oxytocin is a neuropeptide synthesized in the paraventricular and supraoptic nucleus of the hypothalamus. Oxytocin is released from axon terminals of the posterior pituitary into the bloodstream. It is also distributed to the central nervous system and oxytocin binding sites are found throughout, especially in the limbic system (Insel and Young, 2000). Oxytocin has been linked to afifiliative behavior, social memory, and behavior, all of which are impaired in autism (Insel et al., 1999). It has been hypothesized that dysfunction of oxytocin and vasopresin contributes to social impairment in autism (Waterhouse et al., 1996). 

Nelson and Bauman (2003) measured numerous neuropeptides in archived neonatal blood of children later diagnosed with autism, mental retardation, cerebral palsy, and controls. They found, in comparison with controls, significant elevations in concentrations of vasointestinal peptide (VIP), calcitonin gene-related peptide (CGRP), brain-derived neurotrophic factor (BDNF), and nerve growth factors (NT4/5) in children with autism and in those with mental retardation without autism. There was no measure that distinguished autism from mental retardation. 

Nelson KB, Grether JK, Croen LA, Dambrosia JM, Dickens BF, Hansen RL, Phillips TM (2000) Neuropeptides and neurotrophins in neonatal blood of children with autism, mental retardation and cerebral palsy. Neurology 54 A247. 

Nelson PG, Kuddo T, Song EY, Dambrosia JM, Kohler S, Satyanarayana G, Vandunk C, Grether JK, Nelson KB (2006) Selected neurotrophins, neuropeptides, and cytokines developmental trajectory and concentrations in neonatal blood of children with autism or Down syndrome. Int J Dev Neurosd. 24 73-80. 

Drs. Peter Kirsch and Andreas Meyer-Lindenberg from Mannheim, Germany, are experts on the prosocial neuropeptide oxytocin and discuss its role in humans and its relevance for autism pathogenesis and therapy. In the chapter The Role of the Noradrenergic System in Autism Spectrum Disorders , Dr. David Beversdorf presents the normal role of norepinephrine and its effects on cognition and the possible dysregulation of norepinephrine in autism and possible treatment with propanolol. 

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