User talk:Srinivas Allanki

= Different signaling pathways of opioid receptors =

Opium was one of the popularly used analgesic and addictive drug. Morphine was identified as a principal component of opium by a German Friedrich Sertuner in 1805 and he isolated it. Its use as an analgesic became very popular and soon it's side-effects came into light. On further research, they found another compound, naloxone with less side-effects. These were all non-endogenous agonists and antagonists. Knowing that these externally administered compounds have specific receptors which turn on the signaling pathway to minimize the pain when bound by them, scientists wondered why are these receptors present in the body in the first place. Then further studies on opioid receptors led to the discovery of three major types of endogenous opiate like proteins enkephalins, endorphins and dynorphins. These were produced from their precursors, proenkephalin A, prodynorphin, pro-opioimelacotin respectively. These opioids bind to the opioid receptors to regulate several pathways via some signaling pathways.

Opioid receptors regulate the release of neurotransmitters, presynaptically i.e.,