From Wikipedia, the free encyclopedia
Endogenous anesthetics
are analogs of anesthetics the body makes that have the properties and similar mode of action of general anesthetics.
[1]
Types of endogenous anesthetics
[
edit
]
Carbon dioxide
[
edit
]
Carbon dioxide
(CO
2
) is an abundant gas produced as the final product of glucose metabolism in animals. CO
2
anesthesia is most frequently used for anesthetizing flies.
[2]
But it has also been considered as a fast acting anesthetic in small laboratory animals.
[3]
In the 1900s, CO
2
anesthesia, known as CO
2
therapy was used by psychiatrists for the treatment of anxiety. The patients would receive 70% CO
2
in combination with 30% oxygen causing rapid and reversible loss of continuousness.
[4]
Ammonia
[
edit
]
Ammonia has also been shown to have anesthetic properties.
[5]
Mechanism of action
[
edit
]
The most abundant endogenous anesthetics are small hydrophobic gaseous metabolites of
catabolism
and likely work through a
membrane-mediated mechanism
of general anesthesia.
In the 1800s anoxia was considered the mechanism of CO
2
anesthesia.
[6]
However, studies in humans showed the opposite, oxygenation of the brain tissue increases with increase CO
2
in the lung.
[7]
More recent studies have shown in bees that anoxia is also not the mechanism.
[8]
In humans, CO
2
raises the threshold of stimulation of the nerve cell, decreases the speed of conduction of impulses along the nerve, and increases the height and prolonged duration of the action potential.
[9]
While the endogenous anesthetics appear to have a similar mechanism of action to inhaled anesthetics, their rapid endogenous metabolism complicates their use in humans. Apart from flies, exogenous compounds have proven more useful for maintaining
general anesthesia
.
History
[
edit
]
The first private demonstration of an anesthetic was carbon dioxide by
Henry Hill Hickman
in a dog cerca 1823.
References
[
edit
]
- ^
Lerner, Richard A. (9 December 1997).
"A hypothesis about the endogenous analogue of general anesthesia"
.
Proceedings of the National Academy of Sciences
.
94
(25): 13375?13377.
doi
:
10.1073/pnas.94.25.13375
.
PMC
33784
.
- ^
Nilson, Theresa L.; Sinclair, Brent J.; Roberts, Stephen P. (October 2006).
"The effects of carbon dioxide anesthesia and anoxia on rapid cold-hardening and chill coma recovery in Drosophila melanogaster"
.
Journal of Insect Physiology
.
52
(10): 1027?1033.
doi
:
10.1016/j.jinsphys.2006.07.001
.
PMC
2048540
.
- ^
Kohler, I.; Meier, R.; Busato, A; Neiger-Aeschbacher, G.; Schatzmann, U. (1 April 1999). "Is carbon dioxide (CO
2
) a useful short acting anaesthetic for small laboratory animals?".
Laboratory Animals
.
33
(2): 155?161.
doi
:
10.1258/002367799780578390
.
- ^
LAVERNE, AA (May 1953). "Rapid coma technique of carbon dioxide inhalation therapy".
Diseases of the nervous system
.
14
(5): 141?4.
PMID
13052042
.
- ^
Brosnan, Robert J.; Yang, Liya; Milutinovic, Pavle S.; Zhao, Jing; Laster, Michael J.; Eger, Edmond I.; Sonner, James M. (June 2007).
"Ammonia Has Anesthetic Properties"
.
Anesthesia & Analgesia
.
104
(6): 1430?1433.
doi
:
10.1213/01.ane.0000264072.97705.0f
.
- ^
Antiquack (1826). "Surgical Humbug".
The Lancet
.
5
(127): 646.
- ^
Moriarty, John D. (April 1954). "EVALUATION OF CARBON DIOXIDE INHALATION THERAPY".
American Journal of Psychiatry
.
110
(10): 765?769.
doi
:
10.1176/ajp.110.10.765
.
- ^
Cressman, Anna; Amsalem, Etya (1 January 2023).
"Impacts and mechanisms of CO
2
narcosis in bumble bees: narcosis depends on dose, caste and mating status and is not induced by anoxia"
.
Journal of Experimental Biology
.
226
(1).
doi
:
10.1242/jeb.244746
.
- ^
Moriarty, John D. (April 1954). "EVALUATION OF CARBON DIOXIDE INHALATION THERAPY".
American Journal of Psychiatry
.
110
(10): 765?769.
doi
:
10.1176/ajp.110.10.765
.
