Neurochemistry is the specific study of neurochemicals, which include neurotransmitters and other molecules such as neuro-active drugs that influence neuron function. There is evidence that the neurotransmitter norepinephrine (NE) might be very important in pathophysiology of anxiety and mood disorders. This book analyses the effect of psychiatric medications on NE system and proposes how the treatment outcome might be improved. Furthermore, Parkinson's disease (PD) is characterised by the degeneration of the dopaminergic nigrostriatal pathway. This book reviews the emerging evidence that points to a future direction of PD aetiology research and discusses the oxidative stress of cytosolic dopamine. Recent research has demonstrated the presence of intrinsic inhibitory mechanisms of axon regeneration in the CNS, and thus presents promising therapeutic strategies for the treatment of patients with CNS injury. This book looks at the molecular mechanisms concerning the inhibition of axon regeneration in the CNS. The role of noradrenaline in interpersonal functioning, and in the adaptive function of human social behaviours is examined as well. Other chapters in this book include a review of the current findings on the relationships between insulin resistance, sympathetic nerve activity and B-adrenoceptor polymorphisms in obesity, hypertension and obesity-related hypertension and a discussion of the diverging roles of dystroglycan and the molecular pathomechanism of neuromuscular diseases caused by defective DG function.