Increase of the ejaculatory potency by the systemic administration of aqueous crude extracts of cihuapatli (Montanoa genus) plants in spinal male rats.

In the present study, evidence on the aphrodisiac activity of Montanoa frutescens and Montanoa grandiflora and a comparison with the aphrodisiac activity of Montanoa tomentosa is presented. By using the fictive ejaculation model in spinal male rats, electromyographic recordings of the genital motor pattern of ejaculation were obtained in the bulbospongiosus muscles and analyzed after the intravenous injection of aqueous crude extracts of Montanoa tomentosa, Montanoa frutescens, and Montanoa grandiflora. Results showed that the systemic administration of the aqueous crude extracts of Montanoa plants elicits a significant increase in the ejaculatory capacity of spinal male rats with very robust ejaculatory motor patterns that included the expression of tonic penile erections and penile movements and the potent expulsion of urethral contents. In conclusion, Montanoa frutescens and Montanoa grandiflora increase the ejaculatory potency with aphrodisiac activity similar to Montanoa tomentosa.

The aqueous crude extract of Montanoa frutescens produces anxiolytic-like effects similarly to diazepam in Wistar rats: involvement of GABAA receptor.

ETHNOPHARMACOLOGICAL RELEVANCE: Cihuapatli is the Nahuatl name assigned to some medicinal plants grouped in the genus Montanoa, where Montanoa frutescens (Family: Asteraceae, Tribe: Heliantheae) is included. The crude extract from these plants has been used for centuries in the Mexican traditional medicine as a remedy for reproductive impairments and mood disorders. Experimental studies have systematically corroborated the traditional use of cihuapatli on reproductive impairments and sexual motivation, however, the effect on mood and "nervous" disorders, remains to be explored. MATERIALS AND METHODS: The anxiolytic-like effect of aqueous crude extract of M. frutescens (25, 50 and 75 mg/kg) was investigated in male Wistar rats evaluated in the elevated plus-maze and compared with several doses of diazepam (1, 2 and 4 mg/kg) as a reference anxiolytic drug. Picrotoxin (1 mg/kg), a noncompetitive antagonist of the GABA(A) receptor, was used in experimental procedures to evaluate if this receptor could be involved in the anxiolytic-like effects produced by M. frutescens. To discard hypoactivity, hyperactivity, or no changes associated with treatments, which could interfere with the behavioral activity in the elevated plus-maze, rats were subjected to the open field test. RESULTS: M. frutescens at 50 mg/kg showed anxiolytic-like activity similarly to 2 mg/kg of diazepam, without disrupts in general motor activity. The anxiolytic-like effect of M. frutescens detected in the elevated plus-maze was blocked by picrotoxin, indicating that GABA(A) receptors are involved in the modulation of this effect. CONCLUSIONS: The results corroborate the use of M. frutescens in folk Mexican ethnomedicine as a potential anxiolytic agent and suggest that this effect is mediated by the GABA(A) receptors. Additionally, some sedative effects with high doses of M. frutescens were detected in the present study.