Failure of the putative neuropeptide Y antagonists, benextramine and PYX-2, to inhibit Y2 receptors in rat isolated prostatic vas deferens

British Journal of Pharmacology
S PaleaE Ratti

Abstract

1. The pharmacological activity of neuropeptide Y (NPY) and some analogues in inhibiting the twitch contractions induced by electrical stimulation (single pulses at 25 V, 0.15 Hz, 1 ms) in the prostatic portion of the rat isolated vas deferens was investigated. The rank order of agonist potency was: PYY > NPY2-36 > NPY > NPY13-36 > NPY18-36 > [Leu31,Pro34]NPY = hPP, which is consistent with the activation of a Y2 receptor. 2. The putative Y1 and Y2 antagonist, benextramine (BXT), incubated at 100 microM for 10 or 60 min, was ineffective against PYY-induced inhibition of the twitch response, suggesting that the prejunctional Y2 receptor in this tissue is different from the postjunctional one reported in the literature to be sensitive to BXT blockade. 3. The putative NPY antagonist, PYX-2, incubated at 1 microM for 20 min, was completely ineffective in antagonizing PYY-induced inhibition of twitches. 4. The twitch response was totally inhibited by suramin (100 microM) but was little affected by prazosin (1 microM). Furthermore, NPY was without effect on the dose-response curve to ATP in resting conditions. Taken together, these results suggest that in our paradigm, NPY inhibits the release of a purinergic neurotransmitter which m...Continue Reading

References

Feb 15, 1992·Proceedings of the National Academy of Sciences of the United States of America·K TatemotoM Shimizu
Sep 10, 1992·European Journal of Pharmacology·N MallardB Spriggs
Oct 29, 1991·European Journal of Pharmacology·H N Doods, J Krause
Mar 1, 1991·Trends in Pharmacological Sciences·P WalkerB Waeber
Jan 1, 1990·Proceedings of the National Academy of Sciences of the United States of America·J FuhlendorffT W Schwartz
Dec 24, 1984·Life Sciences·T E AdrianS R Bloom
Nov 14, 1994·European Journal of Pharmacology·C MelchiorreS Ferri
Jan 1, 1994·Naunyn-Schmiedeberg's Archives of Pharmacology·R Bültmann, K Starke
Feb 17, 1995·Life Sciences·C P Wan, B H Lau

❮ Previous
Next ❯

Citations


❮ Previous
Next ❯

Related Concepts

Related Feeds

Anthelmintics

Anthelmintics or antihelminthics are a group of antiparasitic drugs that expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them and without causing significant damage to the host. Discover the latest research on anthelmintics here.

Anthelmintics (ASM)

Anthelmintics or antihelminthics are a group of antiparasitic drugs that expel parasitic worms (helminths) and other internal parasites from the body by either stunning or killing them and without causing significant damage to the host. Discover the latest research on anthelmintics here.

African Trypanosomiasis

African trypanosomiasis, also known as sleeping sickness, is an insect-borne parasitic disease of humans and other animals. It is caused by protozoa of the species Trypanosoma brucei and almost invariably progresses to death unless treated. Discover the latest research on African trypanosomiasis here.