Preliminary screening of plants used in South Africa as traditional herbal remedies during pregnancy and labour.

Agapanthus africanus, Pentanisia prunelloides and Gunnera perpensa are indigenous plants which are used in traditional herbal remedies during pregnancy and childbirth. A crude decoction of each plant was tested on isolated rat uterus and ileum for pharmacological activity. Agapanthus africanus and Pentanisia prunelloides exhibited direct smooth muscle activity on the uterus and ileum preparations, while Gunnera perpensa showed direct smooth muscle activity on the uterus only. All the plant extracts potentiated the initial response of the uterus to oxytocin but Pentanisia prunelloides reduced the maximum response of the uterus to oxytocin. The Agapanthus africanus and Pentanisia prunelloides extracts potentiated the initial response of the ileum to acetylcholine but all the plant extracts inhibited the maximum response of the ileum to acetycholine.