dynorphins การใช้
- Different dynorphins show different receptor selectivities and potencies at receptors.
- They include endorphins, enkephalins, dynorphins and endomorphins.
- Shirayama et al . concluded that both dynorphins A and B were important in stress response.
- Immobilization stress causes increases levels of both dynorphins A and B in the hippocampus and nucleus accumbens.
- The first clues to the functionality of dynorphins came from Goldstein et al . in their work with opioid peptides.
- Dynorphins exert their effects primarily through the ?-opioid receptor ( KOR ), a G-protein-coupled receptor.
- Shirayama et al . used several animal depression models in rats to describe the effects of dynorphins A and B in depression.
- Dynorphins are stored in large ( 80-120 nm diameter ) dense-core vesicles that are considerably larger than vesicles storing neurotransmitters.
- Although dynorphins are found widely distributed in the CNS, they have the highest concentrations in the hypothalamus, medulla, pons, midbrain, and spinal cord.
- Sharma and Alm found that subjecting rats to heat ( 38?C ) caused dynorphins to be upregulated in the cerebral cortex, hippocampus, cerebellum, and the brain stem.
- The authors found that learned helplessness increases the levels of dynorphins A and B in the hippocampus and nucleus accumbens and that injecting KOR antagonist norBNI induces recovery from learned helplessness.
- The "'?-opioid receptors "'( "'MOR "') are a class of opioid receptors with a high affinity for enkephalins and beta-endorphin, but a low affinity for dynorphins.
- Through activation of the KOR, dynorphins, opioid peptides that are the endogenous ligands of the KOR and that can, in many regards, be figuratively thought of as functional inverses of the morphine-like, psychiatric conditions in humans.