Systemic naloxone had no significant effect on the inhibi-tion produced by CP stimulation. Systemic methysergide reduced or eliminated the in-hibition in a part of the neurons tested, suggesting that 5--HT, but not opioid Peptides,is involved partially in mediation of the descending inhibitory effect originating fromthe cortex.
While developing an assay on binding of β-EP to plasma membrane in rat uterus we witnessed evidence of extensive peptide proteolysis that was quite different from the opiate receptor rich brain membranes. Uteri were removed from adult Sprague- Dawley rats, homogenized in 50mmol/L of Tris-HCl buffer. pH 7.5 (TB), centrifuged (12 000g) and the pellet was resuspended in TB containing glycerol.
In the presence of an opioid analog,DAMA(10(-13)~10(-10)mol/L),human granulocytes and Mytilus edulis immunocytes were incubated with or without ligands at 37℃ for 10 minutes and at 23℃ for 20 minutes, respectively.
The purpose of this study was to determine whether the endogenous opioid peptide dynorphin A(1-13) has a direct effect on the heart or acts to modulate the cardiac chronotropic response to calcium, potassium, or β-adrenergic receptor stimulation.
Ethanol induces differential alterations in opioid peptide expression in brain areas of the reward circuits, which may be linked to the reinforcing effects of ethanol.