Penile erection inducedin vivoby a purified toxin from the Brazilian spiderPhoneutria nigriventer
| Autor: | Lanfranco R.P. Troncone, Leonardo Messina, Enrico Andrade, Miguel Srougi, Katia R. M. Leite, Priscila Borra, Joaquim F.A. Claro, Fabiola E. Villanova, Mario Paranhos, Italo Cortez |
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| Rok vydání: | 2008 |
| Předmět: |
Male
medicine.medical_specialty Ratón Muscle Relaxation Urology medicine.medical_treatment Spider Venoms Neuropeptide Erectile tissue Mice In vivo Internal medicine medicine Animals Saline business.industry Penile Erection Neuropeptides medicine.anatomical_structure Endocrinology Mechanism of action medicine.symptom Phoneutria nigriventer business Penis |
| Zdroj: | BJU International. 102:835-837 |
| ISSN: | 1464-410X 1464-4096 |
| DOI: | 10.1111/j.1464-410x.2008.07762.x |
| Popis: | OBJECTIVES To verify the effect on erectile tissue of mice of two neuropeptides extracted from the poison of a spider, Phoneutria nigriventer, (Tx2-5 and -6, termed ‘eretina’) after direct injection into the corpus cavernosum, to assess the minimum dosage necessary for effect, the time for initiation of action, the local duration of the erection, histological effects and the presence of local and systemic side-effects. MATERIALS AND METHODS When applied intraperitoneally, eretina promotes the relaxation of cavernous smooth muscle, thus causing penile erection. Thirty-five mice were divided in two groups; 10 control mice were injected 20 µL of saline solution, and in the treated group, 25 mice were divided into groups of five and each subgroup received eretina in decreasing doses (0.024, 0.012, 0.006, 0.003 and 0.0015 µg/kg) until the minimum dose that produced an erection was determined. After treatment all mice were monitored to determine the response and any collateral effects. RESULTS The minimum dose producing an erection was 0.006 µg/kg, the five mice in this group having evidence of an erection at 35–45 min after injection. The histology of the cavernosum of mice treated with eretina showed dilatation and congestion of the vascular spaces with more blood than in controls. With the minimum dose there were no local or systemic collateral effects and the erection was lost after 120–140 min. CONCLUSION The minimum dose of eretina producing an erection in mice was determined, and the agent was safe for this use as it did not produce any collateral toxic effects. These studies indicate a possible means of determining the mechanism of action of eretina. |
| Databáze: | OpenAIRE |
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