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Neuromolecular imaging (NMI) visually links electrical and chemical brain activity with neurotransmitter release in vivo, in real time and online to identify biomarkers to diagnose and treat neurodegenerative disorders such as Parkinson's disease (PD). NMI combined with BRODERICK PROBE laurate nanobiosensors image neuromolecules as the molecular transmitter crosses synaptically in the same motor neurons in basal ganglia as striatal motor neurons in basal ganglia direct movement. With NMI, striatal motor neurons function as electrical devices to synchronize instantaneously with the BRODERICK PROBE nanobiosensor to signal functional physiology (non-PD) or dysfunctional pathology (PD). In non-PD, neurons signal monoamines, precursors, and metabolites selectively with and without L-3,4-dihydroxyphenylalanine ( l -DOPA), while in PD, neurons signal peptides revealing the likely etiology of PD as the BRODERICK PROBE sees inside the PD brain and allows a direct cause and effect in PD per se and then further provides a direct online image inside the non-PD brain. NMI studies were further contrasted with PD versus non-PD responses after administration of the pharmaceutical, indirect agonist, bromocriptine (Parlodel). PD and non-PD animals were videotracked, and images were readily seen on a laptop via a potentiostat using a semiderivative electrical circuit. PD lesions with 6-hydroxydopamine (6-OHDA) were performed in substantia nigra pars compacta by Charles River surgeons. Administered l -DOPA doses were 50 and 100 mg/kg intraperitoneally; the same experimental paradigm was used to image PD versus non-PD animal models. Results showed that the baseline release of biogenic amine molecules was significantly above detection limits in non-PD animals and further increased dramatically in a linear dose response pattern after l -DOPA administration, whereas the PD model showed distinct pathology for baseline signally in basal ganglia. There were little or no biogenic amines. In fact, peptides and amino acid, l -tryptophan, were signaled instead of biogenic amines; and after l -DOPA, dramatic off-scale peptide and amino acid release was imaged, and the response was nonlinear. Indeed, there was no statistical difference between responses after the low dose in contrast to the higher dose l -DOPA in the PD animal model. Thus, NMI demonstrates for the first time that the actual online absence of the biogenic amine, catecholamine, dopamine, and the periodic absence of the indoleamine, serotonin, are empirical biomarkers for PD. Significant biomarkers present in PD and absent in non-PD animals include peptide neurotransmitters, dynorphin and somatostatin; l -DOPA significantly increased dynorphin, a glutamate toxin, and somatostatin, a protector in PD, but could not enable release of catecholamines or indolamines. It is intriguing that PD animals released the precursor to serotonin, that is, l -tryptophan, to a strikingly similar degree as was seen in signals imaged for the peptide biomarkers in PD, showing that the neurotransmitter biogenic amine, serotonin, as well at l -tryptophan, and the absence of dopamine are live biomarkers for PD, in fact, as critical as are the peptide biomarkers. The data enable cutting-edge and never-before-shown advances in the field of PD and nanobiotechnology specifically for unique diagnostic, surgical, and pharmacotherapeutic relief from debilitating PD.

Compounds that have the property to disrupt the neuroendocrine signaling and the metabolisms of hormones and neuromediators in organisms are termed neuroendocrine disrupters. Previously named endocrine disrupters, the scientific community realized that many neuromediators are also involved in other systems or functions such as growth, food intake (behavior), gonad development, and sexual differentiation. These observations suggested that neural and endocrine signaling, especially those involved in reproduction, were associated or physiologically coupled. Estrogenic compounds capable of acting as estrogen mimics in respect to biochemical targets in cells are by far the most studied type of endocrine disrupters in the wild. Indeed, estrogen binding to receptors leads to important physiological changes, including the mobilization of energy reserves and the production of vitellogenin, the egg-yolk protein precursor in oviparous organisms. Vitellogenin represents the main food source for the developing embryos post hatch. This response could also be obtained in males or in juveniles. Expression of vitellogenin in males was also the first step leading to intersex or male feminization in fish and mussels. Both generic and specific assays to detect for the presence of estrogenic effects and estradiol-17β binding sites in aquatic organisms are presented. The evaluation of catecholamines (dopamine and noradrenaline) and indolamines (serotonin) using less specific (fluorescence assay) and more specific means (competitive immunoassay) is also presented to accommodate various laboratory sizes and budgets. Finally, some enzyme-based assays are also presented for acetylcholine and catecholamine/indolamine turnover studies using prepared nerve button synaptic membranes, which are operationally termed synaptosomes.

In this study we investigated the effects of maternal Δ9-tetrahydrocannabinol on the developing serotonergic system. A daily dose of Δ9-tetrahydrocannabinol (5 mg/kg body weight) was administered p.o. to pregnant rats from gestational day 5 to postnatal day 1. Levels of indolamines were measured in four brain areas of the offspring on the day before or after birth. Levels of indolamines depended on the cerebral area, sex and pre- or postnatal age. Maternal exposure to Δ9-tetrahydrocannabinol decreased diencephalic levels of 5-hydroxytryptamine (5-HT), males being more susceptible than females. These perinatal changes could be responsible for the long-term neurophysiological alterations produced by cannabinoids.

Publisher Summary The chapter describes the experiments of intracellular recording from pineal photoreceptors of the trout. The hyperpolarizing nature of their photoresponses, similar to retinal photoreceptors, are confirmed and presents evidence that they are the result of a membrane conductance decrease, as reported in preliminary form. In addition, 3 isobutyl-1-methylxantine (IBMX), a potent phosphodiesterase inhibitor alters the photo responses in accordance with the effects observed in the amphibian retina. A significant difference between the two photoreceptor types with regard to their light adaptation properties was found. Thus, pineal photoreceptors produce constant amplitude responses to prolonged illumination, without showing the characteristic, time-dependent membrane potential changes measured in retinal receptor cells under similar circumstances. These results are discussed in relation to the pineal photoreceptor role in the synthesis and secretion of indolamines.

Publisher Summary The sex differences that are found in neuronal connectivity suggest that such differences may also be expected with respect to the neurotransmitter content measured within sexually dimorphic areas. This chapter discusses the various aspects of the study of sex differences in neurotransmitter systems, and the vasopressin innervation of the brain is discussed as an example of the use of immunocytochemistry in studying sex differences. Several methods have been developed for studying the anatomy of neurotransmitter systems: (i) the histofluorescent demonstration of the indolamines and catecholamines, (ii) enzymes histochemical procedures for cholinergic neurotransmitter pathways, and (iii) immunocytochemistry, which is potentially the most versatile method, because it does not depend on the detailed knowledge of either the chemical nature or the metabolizing enzymes for a given neurotransmitter. Studies of the vasopressinergic innervation of the brain have demonstrated that immunocytochemistry in conjunction with tracing and lesion studies forms a powerful tool to study the anatomical background of a particular sex difference. However, one major problem of immunocytochemical methods is that it is difficult to raise an antiserum, which is directed specifically against a single antigen, which makes it necessary to extensively test all sera and, if necessary, to purify them. An advantage of the application of immunocytochemistry is that it can readily be combined with other techniques, for example, with steroid receptor labeling. The study of the neurotransmitter content of the various components of a given sexually dimorphic system can also help to elucidate its functional significance, if only because the knowledge about the neurotransmitters involved makes it possible to use pharmacological tools, such as local administration of specific agonists or antagonists.

Publisher Summary Although “the profession of the pineal is to regulate reproduction whereas its avocation is to influence the functioning of other endocrine organs,” yet some other target organs can be envisaged, and some new insights may be obtained. The different responses may be tentatively attributed either to the secretion by the epithalamo-pineal complex of several indolederivatives, acting altogether differently than MLT alone, and/or to an activation of eventually melatonergic nerves to the bone marrow. The long latency of the blood platelet increase suggests that MLT or the epithalamic indolamines induce an acceleration of the development from stem- to adult cells, and/or from megakaryocytoblast to mature megakaryocyte. This chapter also presents various other perspectives in pineal functions and in conclusion outlines the results obtained.

Publisher Summary The results presented in this chapter show that it is possible to differentiate between catechol and indolamines in synaptic vesicles. Two methods have been successfully assayed in the pineal nerves of the rat, one of them based on the use of current fixation methods combined with pharmacological treatment and the other using a histochemical technique. After both fixation methods, the typical population of clear and granulated vesicles could be observed with minor differences such as a greater density of the intermediate type of vesicles after glutaraldehyde-osmium tetroxide and darker and better defined cores of the small vesicles after osmium tetroxide alone. However, the heterogeneity of monoamine-containing vesicles as revealed by current and special fixation methods indicates that these results cannot be extrapolated to other granulated vesicles without demonstration. The chapter also shows that different fixatives may preserve different components in synaptic vesicles even if they give a similar picture at the electron microscopic level. Not only employed the fixative but also the used precise schedule may involve substantial differences in the preservation of monoamines. Differences in binding may be an important parameter in the localization of monoamines in synaptic vesicles.

This chapter investigates the origin of the nerve fibers innervating the pineal gland, particularly the nature of the granular vesicles present in the nerve endings. For this purpose, two principal approaches are used: some rats are submitted to the bilateral extirpation of the superior cervical ganglia and some are submitted to the action of drugs that may alter the metabolism of catechol and indolamines. In both cases, the glands are fixed and studied under the electron microscope, and the changes occurring in the nerve fibers and endings are recorded. Preliminary determinations of 5-hydroxytryptamine (5-HT) content are also carried out in normal and denervated glands and in some of the rats treated with agents that may change the content in this indolamine. The chapter presents the results in an extended form. The chapter discusses the actions of other drugs, such as dopamine (DOPA) 5-hydroxytryptophan (5-HTP), α-methylmetatyrosine, aramine, and nialamide on the ultrastructure of nerve endings and on the 5-HT content of the gland.

Publisher Summary This chapter describes the occurrence of indole amines in the pituitary proper of mammals, excluding the median eminence region. The localization of the serotonin in pituitary cells is not established yet, but a new fluorigenic substance, which was not identical with either catecholamines or serotonin, was recently found. This compound has some similarities to the fluorescence characteristics of peptides with tryptophan in the NH,-terminal position. The possible functional significance of local monoamines in the control of pituitary secretion is also discussed. Investigations undertaken to clarify this question showed that peptides with tryptophan in the NH,-terminal position react in the formaldehyde-ozone procedure to give an intense fluorescence spectrally similar to that of tryptamine. It remains to be determined whether N-terminal tryptophyl peptides actually exist in the pituitary and whether these peptides are responsible for the pituitary fluorescence. At present there are no experimental data relating the piuitary stores of serotonin, tryptamine, or histamine to the secretion of pituitary hormones.