| Serotonin receptors: guardians of stable breathing Trends in Molecular Medicine, Volume 9, Issue 12, 1 December 2003, Pages 542-548 Diethelm W. Richter, Till Manzke, Bernd Wilken and Evgeni Ponimaskin Abstract Disturbances of breathing arising from failures of the respiratory center are not uncommon. Among them, breath holding and apnea occur most frequently as consequences of pulmonary and cardiac diseases, hypoxia, head trauma, cerebral inflammatory processes, genetic defects, degenerative brain diseases, alcoholism, deep anesthesia and drug overdose. They are often life-threatening and fail to respond to existing pharmacotherapies. After extensive research, there is now a reliable basis for new strategies to treat respiratory disturbances by pharmacological manipulation of intracellular signaling pathways, particularly those involving the serotonin receptor family. Specific activation of these pathways effectively prevails respiratory disturbances and can be extended to treatment of life-threatening respiratory disorders in patients. Abstract | Full Text | PDF (1299 kb) |
| Lipodystrophy associated with highly active anti-retroviral therapy for HIV infection: the adipocyte as a target of anti-retroviral-induced mitochondrial toxicity Trends in Pharmacological Sciences, Volume 26, Issue 2, 1 February 2005, Pages 88-93 Francesc Villarroya, Pere Domingo and Marta Giralt Abstract The lipodystrophy syndrome and associated metabolic alterations are the most prevalent adverse effects in HIV-infected patients taking highly active anti-retroviral therapy (HAART). This syndrome involves profound disturbances in adipose tissue. The toxic effect of nucleoside reverse transcriptase inhibitors on mitochondrial function is a major contributor to the lipodystrophy syndrome. Although adipocytes were not expected to be preferential targets of mitochondrial toxicity, recent re-evaluation of the role of mitochondria in white adipocytes helps to explain the molecular basis of HAART-associated lipodystrophy. Adipocytes are a source of paracrine and endocrine signals that influence adipocyte biology and systemic metabolism. Mitochondrial disturbances elicited by HAART result in an abnormal perception of the bioenergetic status by adipocytes, thus leading to enhancement of catalytic pathways and apoptosis in peripheral adipose tissue, alterations in the differentiation of brown versus white adipocytes, and the release of hormonal signals that lead to systemic metabolic disturbances. Abstract | Full Text | PDF (255 kb) |
| Ca, mitochondria and selective motoneuron vulnerability: implications for ALS Trends in Neurosciences, Volume 28, Issue 9, 1 September 2005, Pages 494-500 Friederike von Lewinski and Bernhard U. Keller Abstract Motoneurons are selectively damaged in amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disorder. Although the underlying mechanisms are not completely understood, increasing evidence indicates that motoneurons are particularly sensitive to disruption of mitochondria and Ca-dependent signalling cascades. Comparison of ALS-vulnerable and ALS-resistant neurons identified low Ca-buffering capacity and a strong impact of mitochondrial signal cascades as important risk factors. Under physiological conditions, weak Ca buffers are valuable because they facilitate rapid relaxation times of Ca transients in motoneurons during high-frequency rhythmic activity. However, under pathological conditions, weak Ca buffers are potentially dangerous because they accelerate a vicious circle of mitochondrial disruption, Ca disregulation and excitotoxic cell damage. Abstract | Full Text | PDF (262 kb) |
Copyright © 1965 The Biophysical Society. All rights reserved.
Biophysical Journal, Volume 5, Issue 1, 27-46, 1 January 1965
doi:10.1016/S0006-3495(65)86701-7
Articles
Howard T. Milhorn, Richard Benton, Richard Ross and Arthur C. Guyton
The respiratory system exhibits the properties of a control system of the regulator type. Equations describing this biological control system have been derived. Transient and steady-state solutions for various CO2 and O2 step input disturbances were obtained utilizing a digital computer and are compared with experimental results. The effectiveness of the respiratory system as a regulator is investigated. Further extensions of the model are suggested.