Penile erection induced in vivo by a purified toxin from the Brazilian spider Phoneutria nigriventer.
BJU Int
; 102(7): 835-7, 2008 Sep.
Article
en En
| MEDLINE
| ID: mdl-18537953
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 microL 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 microg/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 microg/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.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Pene
/
Venenos de Araña
/
Neuropéptidos
/
Erección Peniana
Límite:
Animals
País/Región como asunto:
America do sul
/
Brasil
Idioma:
En
Revista:
BJU Int
Asunto de la revista:
UROLOGIA
Año:
2008
Tipo del documento:
Article
País de afiliación:
Brasil
Pais de publicación:
Reino Unido