Introduction to biological and molecular psychiatry

An introduction to biological and molecular psychiatry is offered, intended for oncology and palliative medicine clinicians. A recent historical perspective is used, beginning with a summary of monoaminergic and cholinergic neurotransmission as understood in the 1980s. One endocrine theory of depression, based on HPA axis dysfunction, is described. Recognition of the limits of these models has led to a deeper molecular psychiatry ‘beyond the synapse’ and to an appreciation of the importance of amino acid neurotransmission. Selective expression of proteins, and their covalent and allosteric modification, is now seen as central to neuroplasticity. The NMDA receptor and excitotoxicity are introduced. The chapter closes with an overview of the amygdala and of hippocampal neurogenesis.

Salivary glands of the sand fly Phlebotomus papatasi contain pharmacologically active amounts of adenosine and 5′-AMP

Salivary gland homogenates of the sand fly Phlebotomus papatasi contain large amounts of adenosine and 5′-AMP, of the order of 1 nmol per pair of glands, as demonstrated by liquid chromatography, ultraviolet spectrometry, mass spectrometry and bioassays. These purines, 75–80 % of which are secreted from the glands following a blood meal, have vasodilatory and anti-platelet activities and probably help the fly to obtain a blood meal. Salivary 5′-AMP is also responsible for the previously reported protein phosphatase inhibitor in the salivary glands of P. papatasi, which is shown to be artifactual in nature as a result of allosteric modification by AMP of the phosphatase substrate used (phosphorylase a).