pharmacy, sarin / organophosphates

sarin / organophosphates

Author	Message
Kevin Ellye #1 / 6	sarin / organophosphates Could someone tell me why the cholonergicly inervated tissues are those that are the most effected from organophosphate poisoning with respect to the adrenegically inervated tissues. Surely both are stimulated as acetylecholine is the preganglionic transmitter for both sympathetic and parasympathetic systems.
Thu, 11 Sep 1997 19:47:06 GMT

Paulus: The Roman God of Dru #2 / 6	sarin / organophosphates In article <k tissues in terms of recptor sites or enzyme inhibition. Paul De La Franier Pharmacy Student University of Toronto Quote: >Could someone tell me why the cholonergicly inervated tissues are those >that are the most effected from organophosphate poisoning with respect to >the adrenegically inervated tissues. >Surely both are stimulated as acetylecholine is the preganglionic >transmitter for both sympathetic and parasympathetic systems. My understanding is that organophosphates bind to and inhibit the function of acetylcholinesterase, which is the enzyme which degrades acetylcholine in the synaptic cleft in muscles. As a result, acetylcholine is not degraded and accumulates where it acts as a constant contractionf the muscles. The muscles controlling respiration are not able to undergo their normal cycle of contraction and relaxation and the organism dies. Other organophosphates bind to the recpetor molecules, preveting acetylcholine from binding to them. In muscles, this again does not allow them to contract in respone to nervous stimulation. I do not believe that organophosphates have any effect on the adrenegically
Sat, 13 Sep 1997 13:08:07 GMT

Hans Neut #3 / 6	sarin / organophosphates Quote: >In article <k tissues in terms of recptor sites or enzyme inhibition. >Paul De La Franier >Pharmacy Student >University of Toronto >>Could someone tell me why the cholonergicly inervated tissues are those >>that are the most effected from organophosphate poisoning with respect to >>the adrenegically inervated tissues. >>Surely both are stimulated as acetylecholine is the preganglionic >>transmitter for both sympathetic and parasympathetic systems. >My understanding is that organophosphates bind to and inhibit the function >of acetylcholinesterase, which is the enzyme which degrades acetylcholine >in the synaptic cleft in muscles. As a result, acetylcholine is not degraded >and accumulates where it acts as a constant contractionf the muscles. >The muscles controlling respiration are not able to undergo their normal >cycle of contraction and relaxation and the organism dies. >Other organophosphates bind to the recpetor molecules, preveting >acetylcholine from binding to them. In muscles, this again does not >allow them to contract in respone to nervous stimulation. >I do not believe that organophosphates have any effect on the >adrenegically (Irreversible) anti-ChE agents like Sarin have also an effect on adrenergically innervated tissues: AcH is the neurotransmitter in the ganglia of both the parasympathic and the sympathic system, and Sarin effects all the sites where AcH is released. Hans Neutel.
Sun, 14 Sep 1997 03:00:00 GMT

S. Casey Laizu #4 / 6	sarin / organophosphates Quote: > Could someone tell me why the cholonergicly inervated tissues are those > that are the most effected from organophosphate poisoning with respect to > the adrenegically inervated tissues. > Surely both are stimulated as acetylecholine is the preganglionic > transmitter for both sympathetic and parasympathetic systems. Adrenergic neurons by definition use norepinephrine as a neurotransmitter not acetylchonline and thus are not affected by acetylcholinesterase inhibitors.
Fri, 19 Sep 1997 03:00:00 GMT

Hans Neut #5 / 6	sarin / organophosphates Quote: >> Could someone tell me why the cholonergicly inervated tissues are those >> that are the most effected from organophosphate poisoning with respect to >> the adrenegically inervated tissues. >> Surely both are stimulated as acetylecholine is the preganglionic >> transmitter for both sympathetic and parasympathetic systems. >Adrenergic neurons by definition use norepinephrine as a neurotransmitter >not acetylchonline and thus are not affected by acetylcholinesterase >inhibitors. Isn't it true that sweatglands are innervated by the sympethatic nervous system using acetylcholine (muscarine receptortype) as a neurotransmitter? My believe is that anti-ChE agents like Sarin will effect all the loci where ACh is released, including the autonomic ganglia of both the sympethatic and parasympethatic system. Hans Neutel
Sun, 21 Sep 1997 03:00:00 GMT

S. Casey Laizu #6 / 6	sarin / organophosphates Quote: > Isn't it true that sweatglands are innervated by the sympethatic nervous > system using acetylcholine (muscarine receptortype) as a neurotransmitter? > My believe is that anti-ChE agents like Sarin will effect all the > loci where ACh is released, including the autonomic ganglia of both the > sympethatic and parasympethatic system. > Hans Neutel Sweat glands are innervated by both the cholinergic and adrenerigic systems. Cholinergic stimulation results in gneralized sweating and adrenergic stimulation results in localized sweating. You are correct in stating that autonomic ganglia of both the parasympathetic and sympathetic systems are cholinergic and thus would both be affected by sarin. Indeed sarin causes stimulation followed by depression or paralysis of all autonomic ganglia. However, most organs have intrinsic activity such as the heart, so that if you remove input from the autonomic system it will continue to function --intrinsic heart beat is about 40 beats per minute. So the symptoms that predominate when exposure to sarin occurs are due to postganglionic cholinergic stimulation rather than paralysis of autonomic ganglia.
Fri, 26 Sep 1997 03:00:00 GMT

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