Association of serotonin and ergot alkaloids on tissue partitioning and contractile response of bovine blood vessels

Authors

• Eriton E. L. Valente, State University of Western Parana, Brazil
• David L. Harmon, University of KentuckyFollow
• John May, University of Kentucky
• Huihua Ji, University of KentuckyFollow
• Ronald J. Trotta, University of KentuckyFollow
• James L. Klotz, US Department of AgricultureFollow

Abstract

Ergot alkaloids can bind serotonin (5-HT) receptors interfering with many physiological functions. However, the mechanism has not been completely established. The objective was to evaluate whether the association of 5-HT and the ergot alkaloid, ergovaline, in a 24-h pre-incubation can affect vascular tissue partitioning and contractile responses. Cross-sections of saphenous veins from five steers were used. In the tissue partitioning experiment, the treatments were the combination of three levels of ergovaline (2.01 × 10⁻⁸ M, 2.01 × 10⁻⁷ M and 2.01 × 10⁻⁶ M) with three levels of 5-HT and a control (5 × 10⁻⁸ M, 5 × 10⁻⁷ M, 5 × 10⁻⁶ M and 0 M). After 24-h exposure to the treatments, the blood vessels were washed. Afterward, the tissues were analyzed for ergovaline and 5-HT concentrations. For the contractility experiment, a parallel set of blood vessels was evaluated in the myograph after 24-h pre-incubation with the respective treatments: 1) no additional compound; 2) tall fescue seed extract (2.01 × 10⁻⁷ M of ergovaline); 3) serotonin (5 × 10⁻⁷ M); or 4) ERV plus 5-HT. The tissue ergovaline increased (P < 0.001) about 27.5-fold when the concentration in the media increased 100-fold (2.01 × 10⁻⁸ M to 2.01 × 10⁻⁶ M). However, the presence of 5-HT did not affect (P = 0.368) tissue ergovaline partitioning. When 5-HT was not added, ergovaline reduced (P < 0.05) the 5-HT concentration in the blood vessel. Pre-incubation with ergovaline reduced contractile response by about 95 % (P < 0.05) and 5-HT did not change its effect. Ergot alkaloid partitioning is associated with reduced tissue 5-HT levels and blood vessel contractility.

Document Type

Article

Publication Date

2026

Notes/Citation Information

2666-027X/Published by Elsevier B.V. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).

Digital Object Identifier (DOI)

https://doi.org/10.1016/j.crtox.2025.100272

Repository Citation

Valente, Eriton E. L.; Harmon, David L.; May, John; Ji, Huihua; Trotta, Ronald J.; and Klotz, James L., "Association of serotonin and ergot alkaloids on tissue partitioning and contractile response of bovine blood vessels" (2026). Animal and Food Sciences Faculty Publications. 96.
https://uknowledge.uky.edu/animalsci_facpub/96