Muscle tone altered

Bronchiolar smooth muscle is sensitive to changes in carbon dioxide levels. Excess carbon dioxide causes bronchodilation and reduced carbon dioxide causes bronchoconstriction. Pulmonary vascular smooth muscle is sensitive to changes in oxygen levels excess oxygen causes vasodilation and insufficient oxygen (hypoxia) causes vasoconstriction. The changes in bronchiolar and vascular smooth muscle tone alter the amount of ventilation and perfusion in a lung unit to return the V/Q ratio to one. 

Altered release. Tetanus is an infectious disease caused by the bacterium Clostridium tetani. This bacterium produces a neurotoxin active on inhibitory synapses in the spinal cord. Motor neurons, which supply skeletal muscle and cause contraction, have cell bodies that lie in the spinal cord. Under normal circumstances, these motor neurons receive excitatory and inhibitory inputs from various sources. The balance of these inputs results in the appropriate degree of muscle tone or muscle contraction. Tetanus toxin prevents the release of gamma amino butyric acid (GABA), an important neurotransmitter active at these inhibitory synapses. Eliminating inhibitory inputs results in unchecked or unmodulated excitatory input to the motor neurons. The resulting uncontrolled muscle spasms initially occur in the muscles of the jaw, giving rise to the expression lockjaw. The muscle spasms eventually... 

The vascular endothelium produces a number of substances that are released basally into the blood vessel wall to alter vascular smooth muscle tone. One such substance is endothelin (ET-1). Endothelin exerts its effects throughout the body, causing vasoconstriction as well as positive inotropic and chronotropic effects on the heart. The resulting increases in TPR and CO contribute to an increase in MAP. Synthesis of endothelin appears to be enhanced by many stimuli, including Ag II, vasopressin, and the mechanical stress of blood flow on the endothelium. Synthesis is inhibited by vasodilator substances such as prostacyclin, nitric oxide, and atrial natriuretic peptide. There is evidence that endothelin is involved with the pathophysiology of many cardiovascular diseases, including hypertension, heart failure, and myocardial infarction. Endothelin receptor antagonists are currently available for research use only. 

Mechanism of Action Anticholinergic alkaloids that inhibit the action of acetylcholine at postganglionic (muscarinic) receptor sites. Morphine (10% of opium) depresses cerebral cortex, hypothalamus, and medullary centers. Therapeutic Effect Decreases digestive secretions, increases GI muscle tone, reduces G1 force, alters pain perception and emotional response to pain. 

On contact with moist membranes, S02 forms sulfurous acid, which is responsible for its severe irritant effects on the eyes, mucous membranes, and skin. Approximately 90% of inhaled S02 is absorbed in the upper respiratory tract, the site of its principal effect. The inhalation of S02 causes bronchial constriction parasympathetic reflexes and altered smooth muscle tone appear to be involved. Exposure to 5 ppm S02 for 10 minutes leads to increased resistance to airflow in most humans. Exposures of 5-10 ppm are reported to cause severe bronchospasm 10-20% of the healthy young adult population is estimated to be reactive to even lower concentrations. The phenomenon of adaptation to irritating concentrations has been reported in workers. However, current studies have not confirmed this phenomenon. Asthmatic individuals are especially sensitive to S02. 

Altered muscle tone Catatonia Muscle tremors... 

Altered muscle tone Increase (f) or decrease (I) Hardness or softness of the abdomen when pressed laterally between forefinger and thumb is compared with controls... 

Because of its activity at muscarinic receptor sites on the iris sphincter and ciliary muscles, pilocarpine causes pupillary constriction and varying degrees of accommodative spasm, depending on the patient s age. Longterm therapy with pilocarpine or other miotics alters iris muscle activity and may cause permanent miosis resulting from loss of iris radial muscle tone and from fibrosis of the sphincter muscle. 

Perhaps the most widely knowm agent to alter cholinergic transmission is the belladonna alkaloid, atropine. This agent is relatively selective for muscarinic receptors and as such decreases exocrine gland secretion, smooth muscle tone and the effects of vagal nerve stimulation of the heart. Atropine has several clinical applications including use as a preoperative medication, post-myocardial infarction to increase heart... 

The question of possible neurobehavioral effects in the child as a consequence of obstetric analgesia is stiU debated although impairment of visual and neurological performance, reduced alertness, and alterations in walking and muscle tone have aU been reported, most authors have found normal Apgar scores and psychomotor development after obstetric anesthesia (SED-12, 253) (157,158), and any functional defects noted at birth are likely to be transient (159). 

Marihuana, A -THC and THC analogues actually induce a variety of neurological effects in normal animals, usually manifested as alterations of motor function and altered locomotor activity, impaired co-ordination and balance, decreased muscle tone and reflexes and, at very high doses, tremors, myoclonic jerks, and convulsions. CBD is very considerably less potent than A -THC in producing these abnormalities [53-56],... 

Aggressiveness toward experimenter Altered muscle tone... 

Not fully understood. In some cases the symptoms seen appear to be consistent with the serotonin syndrome, which is typified by CNS irritability, increased muscle tone, shivering, altered consciousness and myoclonus, and appears to be associated with the use of more than one serotonergic... 

From the perspective of hormonal influences on brain and systemic function via the influence on all three legs of the neuroendocrine immune system, alterations in somatic function become more easily understood. This relationship is best expressed via the autonomic systems structural influence and can be detected as increases in muscle tone, diaphoresis, hypervigilance, hyperesthesia, increased heart rate, and the increased frequency and severity of mood swings (up-reg-ulated sympathetic drive). 

It is at night when the changes in pulmonary mechanics and control of breathing, which occur in healthy individuals during sleep, are superimposed on patients whose conditions are characterized by altered pulmonary mechanics and control of breathing (9). This is especially important during rapid eye movement (REM) sleep when there is loss of intercostal muscle tone, decreased chemoresponsiveness, a rapid shallow breathing pattern,... 

Kotlikojf These animals have an altered contractile response to agonists in vitro. This is about as much as we can say at the moment. We do see a phenotype in terms of their contractile properties. In the RyR2 knockouts we would expect to have a loss of stretch-induced Ca2+ release and CICR in smooth muscle. If you have normal pressurized vasomotor responses in those animals, I think this would suggest that the phenomenon that we have described is not essential for myogenic tone. 

The injection of a vasoconstrictor, which causes an increase in mean arterial blood pressure, results in activation of the baroreceptors and increased neural input to the cardiovascular centers in the medulla oblongata. The reflex compensation for the drug-induced hypertension includes an increase in parasympathetic nerve activity and a decrease in sympathetic nerve activity. This combined alteration in neural firing reduces cardiac rate and force and the tone of vascular smooth muscle. As a consequence of the altered neural control of both the heart and the blood vessels, the rise in blood pressure induced by the drug is opposed and blunted. 

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