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F C Tulunay

Publications and source records attributed to F C Tulunay.

44 records · Page 3Linked to original sources
PubMedDate not supplied

Dynorphin(1-10)amide: a potent and selective analog of dynorphin(1-13).

Dynorphin(1-10)amide was more potent than Dynorphin(1-13) in inhibiting the twitch of the mouse vas deferens (IC50 of Dynorphin(1-10)amide = 0.3 nM and IC50 of Dynorphin (1-13) = 4.0 nM). Binding assays indicated that two opioid peptides had similar profiles in that they enhanced dihydromorphine (DHM) binding in picomolar concentrations but displaced DHM binding in nanomolar concentrations (IC50 for Dynorphin(1-10)amide = 5 nM). In the mouse tail-flick assay, however, Dynorphin(1-10)amide showed a more selective action on morphine-induced analgesia. Although Dynorphin(1-10)amide had no significant analgesic activity by itself, it differed from the (1-13) analog by neither potentiating nor antagonizing morphine in naive animals. In tolerant animals, on the other hand, 50 microgram of this analog administered icv shifted the ED50 of morphine from 43.0(33.0-55.9) to 17.0 (12.4-23.3). Thus, Dynorphin(1-10)amide appears to be a more potent and selective analog of Dynorphin(1-13).

Analgesia↗
PubMedDate not supplied

Pro-enkephalin intermediates in bovine brain and adrenal medulla: characterization of immunoreactive peptides related to BAM-22P and peptide F.

Using antibodies against the synthetic opioid peptides BAM-22P and peptide F, immunoreactive (ir-) peptides were measured in bovine brain and adrenal medulla. In addition to the high levels in the adrenal medulla, both ir- peptides were measurable in various areas of the brain with highest concentrations in the anterior hypothalamus. Analysis of the ir- components by gel filtration revealed molecular heterogeneity. Besides peptides with the size of BAM-22P or peptide F, various higher molecular weight species were found. These forms were found in the adrenal medulla in much higher concentrations than in the brain indicating a different processing mechanism for proenkephalin. Synthetic BAM-22P injected intracerebroventricularly into mice produces a substantial analgesia (ED50 6.4 nmole) which is almost as high as that of morphine (ED50 2.8 nmole). This finding and the presence of BAM-22P-like compounds in the brain suggests a role of the enkephalinergic system in pain transmission.

Adrenal Medulla↗