Abstract

The effects of GABA and selective GABAA and GABAB receptor agonists and antagonists have been investigated on field stimulation-induced contractions (0.1 Hz) of rabbit urinary bladder strips in-vitro. Atropine inhibits twitches of bladder strips obtained from the bladder dome more effectively than those obtained from the bladder base. Both GABA and the selective GABAB receptor agonist, (+/-)-baclofen inhibited field stimulation-induced contractions to about the same extent, while the selective GABAA receptor agonist, homotaurine had no effect. In the presence of atropine, GABA failed to inhibit further the amplitude of twitches. The effects of either GABA or (+/-)-baclofen were antagonized by the GABAB receptor antagonists homotaurine and 5-aminovaleric acid, while the GABAA receptor antagonist picrotoxin had no effect. Neither GABA nor (+/-)-baclofen had any significant effect on acetylcholine-induced contractions of unstimulated bladder strips, but they were abolished by atropine. These results suggest that GABAB receptors inhibit field stimulation-induced contractions of rabbit bladder muscle by reducing the amount of acetylcholine released per nerve impulse.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.