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Structural Methods in the Study of Development of the Lung
Published in Joan Gil, Models of Lung Disease, 2020
Paul Davies, Daphne deMello, Lynne M. Reid
In the epithelium itself nine types of cell have been identified: mucous, serous, Clara, neuroendocrine, basal, brush, ciliated, intermediate, and special (Jones and Reid, 1979; Reid and Coles, 1984). The first three secrete some of the constituents of mucus and provide material for the mucociliary escalator. Neuroendocrine cells secrete neurohormones. The others serve a variety of functions, from progenitor cells to transport and absorption, all of which have been reviewed (Reid and Coles, 1984). The relative proportions of the various cell types differ at different airway levels and the normal ratios can be altered by exogenous agents and in disease.
Changing the Paradigm from Neurochemical to Neuroelectrical Models
Published in Hanno W. Kirk, Restoring the Brain, 2020
Neuromodulators are typically released from neurons and affect groups of other neurons or effector cells that have appropriate receptors. These often act through what are known as second messengers. Neurohormones, on the other hand, are released from neurons into the circulation and affect cells at a distant site. An example of this would be the release of oxytocin from the neurohypophysis to induce labor. It is important to note that many such receptors previously thought to reside only within the nervous system have also been found in the gut, the circulatory system, and the immune system. The chemical messenger model posits that brain function is dependent on proper “levels” of neurochemicals within its circuitry. For example, it has long been thought that low levels of the neurotransmitter serotonin are responsible for symptoms of depression. Further, it has been demonstrated that molecules such as enkephalins and endorphins are important in mediating pain transmission at both physical and psychological levels. Moreover, endorphins may be involved in what is popularly referred to as the “runner’s high”, because vigorous exercise may stimulate its release. A huge proportion of the pharmaceutical industry is based on manipulation of neurochemistry to alter brain function.
What is the evidence for psychobiological harm from the use of ‘ecstasy’ (MDMA)?
Published in Philip N. Murphy, The Routledge International Handbook of Psychobiology, 2018
Carl Alexander Roberts, Catharine Montgomery
MDMA’s agonist action on serotonin also leads to stimulation of the hypothalamic–pituitary–adrenal (HPA) axis, resulting in altered neuroendocrine function (Parrott et al., 2008). The neurohormone cortisol is understood to be produced in response to stress, and has been used as an indicator of neuroendocrine function. Acute effects of MDMA, combined with dancing in hot environments, have been reported to increase salivary cortisol levels by up to 800% compared to clubbing without taking the drug (Parrott et al., 2008). This combination of drug use and prolonged dancing in hot environments is proposed to have an interactive effect on psychobiological functions, which has been termed the ‘bioenergetic stress model’ of recreational MDMA use (Parrott, 2006; Parrott et al., 2008). Moreover, MDMA has been described as an acute metabolic stressor, due to its action on cortisol (Parrott, 2006; Parrott et al., 2008). Further evidence for acute increases of cortisol after MDMA use comes from de la Torre et al. (2000) who observed marked elevation of plasma cortisol and prolactin after doses of MDMA that are equivalent to recreational doses (50–150mg). Peak cortisol concentration was observed two hours post-ingestion. Harris et al. (2002) report similar significant increases in plasma cortisol after administration (1.5mg/kg) of MDMA in humans.
Developmental exposure to the A6-pesticide causes changes in tyrosine hydroxylase gene expression, neurochemistry, and locomotors behavior in larval zebrafish
Published in Toxicology Mechanisms and Methods, 2022
Ahmed Nasri, Pierre-André Lafon, Amine Mezni, Philippe Clair, Nicolas Cubedo, Ezzeddine Mahmoudi, Hamouda Beyrem, Mireille Rossel, Véronique Perrier
TH has been used as a biomarker for dopaminergic neurons since it is a dopamine synthesis enzyme (Pickel et al. 1975). Dopamine is considered is a neurohormone and neurotransmitter that plays a crucial role in regulating animal life by acting in both the central and peripheral nervous systems (Ugrumov et al. 2012). Dopamine in the peripheral nervous system has been reported in the kidneys, carotid bodies, peripheral arteries, and parts of the gastrointestinal, genitourinary, and endocrine systems (Pivonello et al. 2007). The monoaminergic neurons use dopamine as a transmitter, and it contributes to a variety of functional processes in the vertebrates (Zagrean 2014). The very wide distribution of dopaminergic cells in the central nervous system illustrates its involvement in a varied range of central functions, such as motivation (Schultz 2002), learning and memory (Goldman-Rakic 1997), affective and emotional processes (Diehl and Gershon 1992), control of body temperature (Cox et al. 1978), and locomotion (Mok and Munro 1998).
The first report of clonidine in vivo/in vitro effects on infertile women with polycystic ovary syndrome (in vivo/in vitro study)
Published in Journal of Obstetrics and Gynaecology, 2022
Farideh Zafari Zangeneh, Samad Muhammadnejad, Mohammad Mehdi Naghizadeh, Mina Jafarabadi, Maryam Sarmast Shoushtari, Masoumeh Masoumi
Sleep disturbance has been reported in PCOS women. The sleep–wake pattern and neurohormone secretion in women is modulated by the menstrual cycle. The menstrual cycle is related to variations in melatonin production (Reiter 1998). The relationship between these variations and ovulation is unknown, yet. Endogenous circadian rhythm (suprachiasmatic nuclei (SCN)) controls melatonin secretion from pineal gland in the reaction to light/darkness. Brain biological clock (SCN) has the genetic programming of the natural rhythms of the sleep/wake cycle. SCN controls animal seasonal reproductivity (Kalsbeek et al. 2012). Several studies have discussed the administration of melatonin and its therapeutic outcomes in women with PCOS (Basheer et al. 2018; Mokhtari et al. 2019). Barron et al. also reported that bipolar disorder (psychopathology) or PCOS (endocrinopathy) were more prevalent in the women with light/dark vulnerability (Barron 2007). Pires-Lapa et al. suggested that the β-adrenoceptors stimulates synthesis of melatonin by stimulating cAMP/protein kinase A (PKA) pathway and activating the nuclear translocation of NF-κB (Pires-Lapa et al. 2018).
The function and mechanism of dopamine in the activation of CD4+ T cell
Published in Immunopharmacology and Immunotoxicology, 2022
Yu Shao, Yongli Dong, Wenwen Wang, Zhengrong Chen, Chuangli Hao, Yi Yang, Jinping Zhang
Dopamine (DA) is an important neurotransmitter in the central nervous system involved in the control of locomotion, emotion, cognition, and neuroendocrine secretion [1]. In the periphery, besides acting as the major neurotransmitter of the sympathetic nerve, DA can also function as a neurohormone. Under normal conditions, plasma contains a low level of DA, most of which is conjugated to sulfate or glucuronide [2]. However, when the body is physically or mentally stressed, DA is released from sympathetic nerve ending and adrenal medulla into the bloodstream, which results in an increase in plasma DA [2]. The role of DA in immune system is suggested by the observation that lymphoid organs are found richly innervated by the sympathetic nerves [3,4], and by the phenomena that some neurological diseases like Parkinson’s disease and schizophrenia with hypo- and hyperactivity of central dopaminergic system are well-correlated with abnormalities of immune functions [5,6]. In addition, it was proposed that short-term stress, one of the nature’s fundamental mechanisms to promote survival during fight or flight, could enhance immunoprotection, while long-term stress suppresses or dysregulates immune responses [7–9]. Moreover, although still inconclusive and even contradictory, the results that DA receptors are expressed on immune cells further support this involvement. Later, it turned out that DA indeed have a broad and various influence in different immune cells, including T cells, B cells and macrophages [10–14].