PubMed Health⌕ Search

Biomedical subjects

E Bejar

Publications and source records attributed to E Bejar.

8 recordsLinked to original sources
PubMed1984

The in vitro effect of grandiflorenic acid and zoapatle aqueous crude extract upon spontaneous contractility of the rat uterus during oestrus cycle.

Montanoa tomentosa (zoapatle) is a Mexican plant popularly used for antifertility purposes and with promising characteristics for the development of a new oral contraceptive agent with uteroevacuant properties. In a previous pharmacological report we established the ambivalent myometrial response to zoapatle leaves aqueous extract (ZACE) depending on the animal species used and on the existence or absence of pregnancy. This fact could be useful in determining an appropriate medical use of zoapatle and suggests an interesting possible hormonal dependence in its mechanism of action. To elucidate the ZACE effect upon the pattern of uterine contractility in different hormonal stages, the rat uterus in vitro during oestrus cycle was studied. The aqueous crude extract of Montanoa tomentosa leaves produced different (or even opposite), effects on uterine motility during the distinct phases of the oestrus cycle in the rat. Furthermore, pure grandiflorenic acid (GA), obtained from the phytochemical work up of this plant reproduced the uterine responses induced by ZACE. The action of zoapatle is discussed in relation to hormonal stage and to a probable adrenergic mechanism involved.

Abortifacient Agents↗
PubMed1983

The zoapatle II--botanical and ecological determinants.

A collection of Montanoa (Cerv) specimens was conducted throughout Mexico. Twenty-one specimens were classified, some of them grown in the greenhouse and transplanted in an agricultural experimental field station in the Valley of Mexico. In vitro uterotonic potency was assayed and the results expressed as equivalents of oxytocine, by using estrogenized guinea pig uterine strips. A great variation of uterotonic potency was observed among the wild plants. A clear decrease and uniformity of uterotonic potency was found in plants grown in the experimental field. The study points out the importance of ecological variations in expression of the plant's biological activity.

Altitude↗
PubMed1983

The zoapatle III--biological and uterotonic properties of aqueous plant extract.

Differences in uterotonic activity were observed between zoapatle Montanoa (Cerv.), plants growing in their natural habitat and plants growing in an experimental agricultural plot. Details of an in vitro analogic model for assaying uterotonic potency in guinea pig strips is described. Important species differences on the uterine response to zoapatle aqueous crude extract were noticed in rats, hamsters, guinea pigs, cats and Rhesus monkeys. The need for proper biological evaluation of chemical substances already isolated from zoapatle specimens, is mentioned, and the advantages of working with zoapatle specimens grown under controlled ecological conditions are pointed out.

Animals↗
PubMed1983

The zoapatle IV--toxicological and clinical studies.

The zoapatle aqueous crude extract has been used in Mexico for the last 5 centuries for the induction of labor, treatment of post-partum bleeding problems, and as a menses inducer. Today, it is sold in street markets, and its long documented history of use by humans could be taken as indirect evidence of a lack of toxicity. Rigorous pharmacological and clinical studies described here, fully confirm the empirical observations.

Animals↗
PubMed1983

The zoapatle V--the effect of kauradienoic acid upon uterine contractility.

Kauradienoic acid was obtained from the hexanic extract of M. tomentosa (Cerv) leaves by chromatographic separation. This substance influenced the in vitro contractility of the rat, dog and guinea pig uterine strips. It also induced strong contractions of the guinea pig uterus in vivo when administered intravenously, without changes on arterial blood pressure. The effects produced by the plant infusion, the hexanic extract and pure species were compared. The hexanic of other utero-active compounds in M. tomentosa in addition to those already described is discussed.

Animals↗