The effects of herbal oxytocics on the isolated “stripped” myometrium model

• Published in: Life sciences (1973) Vol. 67; no. 11; pp. 1381 - 1388
• Main Authors: Veale, D.J.H., Oliver, D.W., Havlik, I.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 04-08-2000
• Subjects: Agapanthus africanus; Animals; Clivia miniata; Female; Herbal remedies; In Vitro Techniques; Labor; Models, Biological; Myometrium; Myometrium - drug effects; Oxytocics; Oxytocin - analogs & derivatives; Oxytocin - pharmacology; Plant Extracts - pharmacology; Plants, Medicinal - chemistry; Pregnancy; Rats; Rats, Sprague-Dawley; Pregnancy; Myometrium; Clivia miniata; Oxytocics; Labor; Herbal remedies; Agapanthus africanus
• ISSN: 0024-3205; 1879-0631
• DOI: 10.1016/S0024-3205(00)00719-0

Decoctions of
Agapanthus africanus and
Clivia miniata are used as oxytocic agents in South African traditional herbal medicine. Aqueous extracts of
A. africanus and
C. miniata leaves have been shown to possess similar uterotonic activities in the isolated whole uterus preparation. The uterus however, comprises a myometrial and an endometrial layer and the activity of both oxytocin and the prostaglandins differs in these layers. The aim of this study was to determine the uterotonic activity of the herbal remedies in an endometrium-free preparation (i.e. “stripped” myometrium) and, if active, whether this effect could be related to prostaglandin synthesis or to interaction with specific receptors. The effects of the herbal extracts were tested on the isolated “stripped” rat myometrium preparation. Both herbal extracts caused a direct contractile response by the isolated tissue. Pretreatment of the myometrium with either plant extract augmented the initial response to acetylcholine. Preincubation with atropine inhibited the response to cumulative dosage of
Agapanthus extract but had no effect on the response to
Clivia. Indomethacin administration did not affect the response of the myometrium to cumulative dosage of acetylcholine, oxytocin or
Clivia extract but inhibited the response to
Agapanthus extract. These results clearly indicate that the
Agapanthus and
Clivia herbal extracts exhibited uterotonic activity in this model. The study illustrates that the “stripped” myometrium model has successfully differentiated between the mechanisms of action of two herbal oxytocics compared to the whole uterus preparation where their uterotonic activity was thought to be similar.