Banca de DEFESA: VICTORIA BESSA ALVARENGA LIMA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : VICTORIA BESSA ALVARENGA LIMA
DATE: 10/08/2022
TIME: 14:00
LOCAL: On-line
TITLE:

Study of the effect of Ginkgo biloba and quercetin extracts on the mouse vas deferens

KEY WORDS:

Herbal medicines; Premature ejaculation; Ginkgo biloba; Quercetin; Vas deferens

PAGES: 75
BIG AREA: Ciências Biológicas
AREA: Farmacologia
SUMMARY:

Medicinal plants have been used because they play an important role in human health.
Ginkgo biloba (GB) is one of the oldest tree species in the world. Its extract (GBE) has
been used in traditional Chinese medicine for about 5000 years to treat different ailments.
It has been demonstrated, the relaxing effect of GBE in different organs of smooth
muscle, however, as far as it has been possible to research, there are still no studies
demonstrating the effect of Ginkgo biloba extract on the vas deferens. The vas deferens
(DD) conducts the spermatozoa at the moment of ejaculation. This event occurs by the
contraction of the smooth muscle cells of the DD, which play an important role in the
emission phase of ejaculation, and changes in this contraction can lead to ejaculatory
disorders, such as premature ejaculation (PE). PE is considered the most common sexual
disorder in the male population, characterized by ejaculation that always or almost always
occurs before or about 1 minute after vaginal penetration. Thus, our objective was to study
the effect of GBE extracts on the contraction of the vas deferens, since alterations in this
contraction may be associated with PE. For this purpose, 60-day-old male Swiss mice
were used. The vas deferens (DD) were isolated and immersed in nutrient fluid in an
organ bath system. Stimulation of contraction, in the DD, was done with potassium
chloride (KCl 80mM). After stabilization of the contractile response, further KCl curves
were performed, but in the presence of increasing concentrations of one of the EGB
extracts (GB1 or GB2) or quercetin, a flavonoid compound present in GB. In addition,
the effect of these substances was also tested in the presence of nifedipine or quercetin.
Our results demonstrate that GB extracts, quercetin and nifedipine are able to inhibit the
phasic and tonic components of KCl-induced contraction. The effect of GB1, under the
tonic component, was potentiated, in the presence of nifedipine. The same happens when
we analyzed the effect of GB2 extract, but in the presence of quercetin. When we
compared the tonic component between the different experimental groups (GB1:
Nifedipine+GB1 or GB2: Nifedipine+GB2 and Quercetin+GB2, we observed that, in the
presence of nifedipine or quercetin, the inhibition of contraction caused by GB1 or GB2
was potentiated when compared with the inhibition that occurs only in the presence of the
extracts. Unlike when comparing the Quercetin and Nifedipine+Quercetin groups, where
there was an increase in the inhibitory effect of quercetin in the presence of nifedipine
under both phasic and tonic components. These results indicate that GB1, GB2 and
quercetin are able to inhibit some mechanism that may be involved with the generation

of KCl-induced contraction in mouse ductus deferens. Furthermore, they also suggest that
this inhibitory effect is not solely dependent on inhibition of voltage-dependent calcium
channels. Thus, these findings point out that GBE as well as quercetin may be
pharmacological strategies for the treatment of PE.

BANKING MEMBERS:
Externo à Instituição - ADOLFO GARCIA ERUSTES
Externo ao Programa - 1908201 - JOAQUIM MAURICIO DUARTE ALMEIDA
Interna - 1811013 - LAILA CRISTINA MOREIRA DAMAZIO
Presidente - 2144084 - PRISCILA TOTARELLI MONTEFORTE