Articles: function.
-
In this paper morphological and physiological experiments are described that refer to the concept of neurogenic inflammation of meningeal structures as a putative source of migrainous pain and other headaches. The main emphasis of this study carried out on the duramater encephali of the rat was the functional role of calcitonin generelated peptide (CGRP), a vasodilatory neuropeptide of fine afferent nerve fibres. Immunocytochemical preparations showed that the parietal dura mater was densely innervated by CGRP immunoreactive nerve fibres, the distribution and ultrastructure of which were examined by ligh and electron microscopy. ⋯ This increase was inhibited in a dose-dependent manner by the competitive CGRP antagonist CGRP(8-37), which shows an involvement of CGRP in the regulation of meningeal blood flow. We conclude that stimulation of trigeminal afferents innervating the dura mater releases CGRP from peptidergic afferent terminals, thereby causing vasodilatation and increasing the meningeal blood flow, an important component of neurogenic inflammation. The preparation decribed will be used for further studies on basic mechanisms of neurogenic inflammation and nociception in meningeal structures.
-
Journal of anesthesia · Sep 1994
Crossover effects of acidosis on the recovery of neuronal function following glucose-oxygen deprivation in rat hippocampal slices.
The present study was designed to determine whether acidosis modifies the effect of simulated ischemia on neuronal function. Hippocampal evoked potentials were recorded in vitro from the CA1 region after stimulation of the Schaffer collaterals and the change in the evoked potentials was analyzed in response to glucose-oxygen deprivation under variable acid-base conditions ranging from pH 7.4 to pH 4.5. ⋯ The recovery of PS amplitude during recovery from glucose-oxygen deprivation was not significantly inhibited by moderate acidosis of pH 6 and 5.5 but was significantly inhibited when the pH was 5 or lower. The results suggest that severe acidosis may depress PS amplitude and prevent their recovery after reversal of glucose-oxygen deprivation, and that moderate acidosis may have no significant effect on PS amplitudes on their recovery.
-
Journal of anesthesia · Sep 1994
Lumbar epidural block reduces cough strength in healthy young subjects.
Effects of lumbar epidural block on maximum expiratory strength were studied in 12 healthy volunteers. Subjects performed maximum expiratory effort against occluded airway at functional residual capacity (FRC) and total lung capacity (TLC) while measuring airway pressure and electromyogram of the abdominal muscles (EMGab). Cough strength was assessed by maximum expiratory pressure (PEmax) and peak EMGab (peak-EMGab). ⋯ Compared with severe reduction in peak-EMGab, PEmax was well maintained at TLC, but changes in PEmax were identical to those in peak-EMGab at FRC. When analgesia spread to higher than T6, PEmax at TLC decreased considerably. We conclude that lumbar epidural block producing analgesia above T6 paralyzes the abdominal muscles and severely impairs the ability of effective cough in healthy young men.
-
In rheumatology, all of the more than 400 specified syndromes are associated with pain. In the conceptual discussion on the multidimensional influences postulated to explain the development of chronic pain, fibromyalgia has gained increasing interest. Fibromyalgia (fibrositis) is an unspecific soft-tissue disorder with chronic wide-spread musculoskeletal pain and palpable hypersensitivity at fibrositic tender points. ⋯ Histochemical investigations on muscle biopsy and biochemical tests have revealed unspecific changes but no characteristic muscle abnormality. It is supposed that the clinical features may result from central neurohumoral dysfunction combining with peripheral mechanisms to result in hyperalgesia. An integrated therapeutic concept with a reassuring and positive doctor-patient relationship can be helpful in achieving satisfactory treatment results.
-
Annals of Saudi medicine · Jul 1994
Antithyroid antibodies and thyroid dysfunction in Saudi children with Down syndrome.
Fifty children (ages seven months to nine years) with Down syndrome compared with age and sex matched controls were tested for antithyroid antibodies. Seven (14%) of the Down group were found to b seropositive; six (12%) for antimicrosomal antibodies; three for both antimicrosomal and antithyroglobulin; none was positive for antithyroglobulin alone. ⋯ Thyroid dysfunction was not previously suspected in the two symptomatic children. In view of our findings, recommendations are made to regularly screen these children for autoantibdies and evidence of thyroid dysfuntion.