Morphine, the principal active agent in opium, is not restricted to plants, but is also present in different animal tissues and cell types, including the mammalian brain. In fact, its biosynthetic pathway has been elucidated in a human neural cell line. These data suggest a role for morphine in brain physiology (e.g., neurotransmission), but this hypothesis remains a matter of debate. Recently, using the adrenal neuroendocrine chromaffin cell model, we have shown the presence of morphine-6-glucuronide (M6G) in secretory granules and their secretion products, leading us to propose that these endogenous alkaloids might represent new neuroendocrine factors. Here, we investigate the potential function of endogenous alkaloids in the central nervous system.

Further transformation led to total synthesis of morphine

08/09/2011 · Synthesis, radiolabeling and biodistribution of morphine glucuronide ..

of total synthesis of morphine from starting materials such as ..

Although granule cells contain the vast majority of dynorphin-immunoreactivity found in the hippocampus, the specific site of dynorphin release was not determined. Release either from recurrent collaterals or from dendrites of the granule cells is possible. Functionally, as the postsynaptic cell is the source of a molecule acting on the presynaptic terminal, dynorphin is acting as a retrograde transmitter. This inhibitory modulation of synaptic transmission mediated by dynorphin may be important in the pathophysiology of the hippocampus, because kappa opioids have been shown to be neuroprotective in excitotoxicity studies. In this role, endogenously released dynorphin could be acting in a compensatory manner to limit hyperexcitability existing during seizure activity. Consistent with this hypothesis is the phenomena of mossy fiber sprouting which occurs in human temporal lobe epilepsies. Contrary to expectations, the time course of this proliferation of mossy fiber recurrent collaterals into the inner molecular layer following a kindling paradigm could not be correlated with an increase in granule cell excitability. Rather, a recovery of inhibition was seen, which is consistent with the inhibitory influence of dynorphin as we have described above. Thus endogenous dynorphin modulation of synaptic activity in the dentate gyrus region may have a prominent role in the pathological and physiological function of the hippocampus.
Numerous studies have described opioid-mediated actions on induction in the two opioid-containing pathways in the hippocampal formation. Although discrepancies among reports have occurred, it can be noted once again that endogenous opioid actions are correlated with high-frequency stimulation events. If one assumes that the phenomena of is representative of learning and/or memory mechanisms, then by analogy with their interactions with endogenous opioids should potentially affect these processes as well.

Endorphin - definition of endorphin by The Free Dictionary

Morphine is one of the 40 alkaloids present in opium from Papaver somniferum, and is one of the strongest known analgesic compounds . Endogenous morphine has been characterized in numerous mammalian cells and tissues , , , and its structure is identical to that of morphine from poppy (for review see , ). In mammals, the biosynthesis of endogenous morphine is associated with that of dopamine and catecholamines , , , , , . Morphine biosynthesis was recently shown in the SH-SY5Y human neuronal catecholamine-producing cell line , , a well-known model for studying neuronal secretion , . Recently, our group has reported the presence of morphine-6-glucuronide (M6G), previously considered a product of morphine catabolism, in the secretory granules and secreted material of bovine adrenal chromaffin cells. In these cells, M6G represents the final product of endogenous alkaloid biosynthesis and is formed through the action of an UDP-glucuronosyltransferase 2B-like enzyme (UGT2B). In chromaffin granules, M6G is bound to the intragranular phosphatidylethanolamine-binding protein (PEBP or Raf kinase inhibitor protein) , which also binds morphine . Secretion of M6G, catecholamines, and PEBP into the blood is likely to occur during stress situations, and could be involved in different stress-modulating or pain-modulating mechanisms via binding to µ opioid receptors (MORs), which are present on numerous cell types , , . Together, all these observations suggest that endogenous alkaloids may represent new neuroendocrine factors .

Endorphin - definition of endorphin by The Free …

Human neuroblastoma SH-SY5Y cells synthesize endogenous morphine and express MORs , , . Therefore, we used this cell line to determine the subcellular localization, biosynthesis, and secretion of morphine.

2nd Endogenous Opiod ID'ed - Means endogenous morphine ..

(better known as ) was synthesized from morphine in 1874 and brought to market by in 1898. Heroin is approximately 1.5–2 times more potent than morphine on a milligram-for-milligram basis. Using a variety of subjective and objective measures, one study estimated the relative potency of heroin to morphine administered intravenously to post-addicts to be 1.80–2.66 mg of morphine sulfate to 1 mg of diamorphine hydrochloride (heroin).

Human White Blood Cells Synthesize Morphine: CYP2D6 …

Endomorphins are two endogenous opioid peptides. Endomorphin-1 is located in the nucleus of the solitary tract, the periventricular hypothalamus, and the dorsomedial hypothalamus, where it is found within histaminergic neurons and may regulate sedative and arousal behaviors. It is assumed that endomorphins are the cleavage products of a larger precursor, but this polypeptide or protein has not yet been identified.
They play important role in perception of pain, responses related to stress and complex functions such as reward, arousal and vigilance, as well as autonomic, cognitive, neuroendocrine and limbic homeostasis.
They have the highest known affinity and specificity for the μ opioid receptor.