Sympathetic nervous system ganglia

The sympathetic nervous system, through hberation of norepinephrine in adipose tissue, plays a central role in the mobilization of free fatty acids. Thus, the increased hpolysis caused by many of the factors described above can be reduced or abolished by denervation of adipose tissue or by ganglionic blockade. 

Yovo et al. stated that these alkaloids act via inhibition of ganglionic impulse transmissions of the sympathetic nervous system. It is evident that each alkaloid has its own effect. Anagyrine caused skeletal deformity in foetuses when pregnant cows consumed toxic lupines . On the other hand, some quinolizidine alkaloids are used as a drug in folk medicine". They probably have chronic toxicity. However, adequate knowledge about the chronic toxicity of these alkaloids and especially of chronic toxication across generations is not available. The premise that quinolizidine alkaloids have not produced hereditary symptoms has not been checked with total reliability. 

In the parasympathetic branch this is nicotine at the ganglia and muscarine at the postganglionic level. In the sympathetic nervous system it is nicotine at the ganglion and noradrenaline and adrenaline at the postganglionic level. 

E. The effect of ganglionic blockade depends upon the predominant autonomic tone exerted within various organ systems. Since the activity of the parasympathetic nervous system predominates in the eye, the effect of ganglionic blockade is mydriasis, not miosis. Similarly, stimulation of the genital tract and urinary retention would be decreased. Since sympathetic nervous system activity predominates in blood vessels and the ventricles, vasodilation and a decreased cardiac output would follow ganglionic blockade. 

Blood vessels receive chiefly vasoconstrictor fibers from the sympathetic nervous system therefore, ganglionic blockade causes a marked decrease in arteriolar and venomotor tone. The blood pressure may fall precipitously because both peripheral vascular resistance and venous return are decreased (see Figure 6-7). Hypotension is especially marked in the upright position (orthostatic or postural hypotension), because postural reflexes that normally prevent venous pooling are blocked. 

Q4 The ganglionic transmitter of both divisions of the autonomic nervous system is acetylcholine. The major postganglionic neurotransmitter of the sympathetic nervous system is norepinephrine (noradrenaline), but a small number of structures are innervated by sympathetic, cholinergic fibres. These fibres release acetylcholine and the structures innervated include the sweat glands and blood vessels supplying skeletal muscle. In the parasympathetic system the postganglionic neurotransmitter is acetylcholine. 

Antagonists of ganglionic nicotinic receptor sites are not therapeutically useful since they cannot distinguish between the ganglia of the sympathetic nervous system and the ganglia of the parasympathetic nervous system (both use nicotinic receptors). Consequently, they have many side-effects. 

The cardiac and renal hemodynamic effects of debrisoquin sulfate have been studied in hypertensive patients and found to be similar to those observed with guanethidine and the ganglionic blocking agents. Lowered blood pressure associated with reduced cardiac output and renal blood flow are apparently characteristic of the hemodynamic pattern of inhibition of the peripheral sympathetic nervous system."... 

Neural components that participate in the regulation of coronary blood flow include the sympathetic nervous system, the parasympathetic nervous system, coronary reflexes, and possibly, central control of coronary blood flow. Within the sympathetic system, stimulation of the stellate ganglion elicits coronary vasodilation, which is associated with tachycardia and enhanced contractility. This indirect coronary vasodilation is secondary to increased MVO2 related to increased heart rate, contractihty, and aortic pressure and occurs following stellate stimulation. The direct effect of the sympathetic system is a 1-mediated vasoconstriction at rest and during exercise. Other receptor types, 2 and have little influence on tone, whereas /32-stimulation produces a modest vasodUatory effect. Although coronary atherosclerosis may decrease blood flow secondary to obstruction, severe coronary atherosclerosis and obstruction also may increase the sensitivity of coronary arteries to the effects of aj-stimulation and vasoconstriction. 

The first works on the pharmacodynamic action of sparteine were by Pick (110) and by Cushny and Matthews (HI). The former author considered that the mode of action of sparteine is essentially central and that it develops in two phases tonic convulsions with decreased respiration—then depression of all motor functions. According to Cushny and Matthews, the action of sparteine is identical with that of conine, with the exception of the central nervous system, which is little affected by the former. Sparteine exerts, above all, a peripheral inhibitory action on the motor nerve endings and on the ganglionic cells of the sympathetic nervous system. 

The preganglionic fibers of the sympathetic nervous system extend from the spinal cord to the ganglionic fiber. These are relatively short. However, sympathetic postganglionic fibers are long from the ganglion to the body cells. 

Sparteine and lupanine, when administered by intravenous rout, inhibit ganglionic transmission of the sympathetic nervous system, assessing their neurotoxicity [17]. 

Cholinergic neurotransmission ChEs terminate cholinergic transmission in the central nervous system (CNS), in NMJs and in the autonomic system (the parasympathetic system, somatic motor nerves and pre-ganglionic sympathetic nerves). A few sensory cells and the NMJ in nematodes also include ChEs. 

Autonomic ganglia. Ganglionic stimulation occurs in both the sympathetic and parasympathetic divisions of the autonomic nervous system. Parasympathetic activation results in increased production of gastric juice (smoking ban in peptic ulcer) and enhanced bowel motility ( laxative effect of the first morning cigarette defecation diarrhea in the novice). 

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