Opium physiological effects

Physiological Effects.—Opium is used modici-nally as a narcotic, sedative, and anodyne, hut it usually acts first as a stimulant, and tho sedative and narcotic effects are apparently the subsequent collapse of (he system. When it excites, the first symptoms are heat, thirst, absence of mind, and sometimes headache and... 

The beginning of alkaloid chemistry is usually considered to be 1805 when F.W. Sertiirner first isolated morphine. He prepared several salts of morphine and demonstrated that it was the principle responsible for the physiological effect of opium, Alkaloid research has continued to date, blit because most likely plant sources have been investigated and because a large number of synthebc drugs serve medical and other needs more effectively, the greatest emphasis has been placed upon the synthetics. 

Or they may be grouped according to the genus of their plant source (morphine and codeine, Section 23-2, are examples of opium alkaloids), or by their physiological effects (antimicrobials, antibiotics, analgesics), or by similarities in the route by which they are synthesized by the organism (biosynthesis). The structural and biosynthetic classifications make the most sense to the chemist and is the organization chosen here. 

The isolation of morphine from opium and the recognition of the significance of its physiological effects by F. W. A. Sertiirner in 1803-1817 as well as the first definition of the term alkaloid by Meissner in 1819-1821 have led to a rapid progress in the research of alkaloids (1). In the beginning of the past century, much attention was paid to the cultivated poppy plant Papaver somniferum L., which has been used since time immemorial in popular medicine. Of the so-far known 41 opium alkaloids, only morphine, codeine, and papaverine have found... 

Solution Morphine is the principle alkaloid of opium and the constituent primarily responsible for opium s physiological effects. Its analgesic and euphoric properties have been a source of study for over hundreds of years. 

The first secondary metabolites that were isolated from natural sources are the alkaloids, these were also the compounds which were the first group of natural products studied systematically by chemists. These compounds were named alkaloids because all of them have nitrogen in their molecules and it is known that nitrogen causes alkaline behavior. As is typical for all secondary metabolites, the molecules of alkaloids can have a wide variety of structures. Many alkaloids induce marked physiological effects, especially on the nervous systans. Some of them like nicotine or components of opium are drugs or have analgesic properties. 

P-Endorphin. A peptide corresponding to the 31 C-terminal amino acids of P-LPH was first discovered in camel pituitary tissue (10). This substance is P-endorphin, which exerts a potent analgesic effect by binding to cell surface receptors in the central nervous system. The sequence of P-endorphin is well conserved across species for the first 25 N-terminal amino acids. Opiates derived from plant sources, eg, heroin, morphine, opium, etc, exert their actions by interacting with the P-endorphin receptor. On a molar basis, this peptide has approximately five times the potency of morphine. Both P-endorphin and ACTH ate cosecreted from the pituitary gland. Whereas the physiologic importance of P-endorphin release into the systemic circulation is not certain, this molecule clearly has been shown to be an important neurotransmitter within the central nervous system. Endorphin has been invaluable as a research tool, but has not been clinically useful due to the avadabihty of plant-derived opiates. 

The very positive nature of the oxidations for 1 and 2 make them unlikely participants in ET. However, other physiologically active compounds possess fairly positive oxidation potentials. For example, the tert-amine of amorphine 9 reacts at about 1.1 2 . It is reasonable to expect stabilization of the cation radical by transannular interaction with the benzenoid nucleus. An ET mechanism for the CNS effects has been proposed29 30, Related opium alkaloids in the codeine (a methyl ether of 9) class react in the range of 1.0 to 1.1 The psychotherapeutic agent... 

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