MECHANISM OF VASORELAXATION INDUCED BY Coptosapelta flavescens STEMS EXTRACT IN RAT THORARIC AORTA
Abstract: Coptosapelta
flavescens Korth. is a liana plant from the Rubiaceae family. In East
Kalimantan, it is also known as “Akar Tambolekar” or “Merung”, it is called
“akar” or root as its trunk spreads like a root. The plant’s stems are used by
ethnic Dayak in East Kalimantan to overcome high blood pressure and it has been
proven to induce vasorelaxation on blood vessels, but the its action mechanism
in the endothelial or vascular smooth muscle cells (VSMC) are unknown.
Vasorelaxation on the blood vessels could be mediated by endothelial or by the
VSMC. This research aims to study in vitro which of them is the mechanism of
action of Coptosapelta flavescens Stems (CFS) extract. CFS were taken from the
secondary forest in Paser Regency, East Kalimantan Province. Its simplicia were
macerated with methanol solvent for three days and twice repeated.
Vasorelaxation activity of the blood vessels was tested with rats’ isolated
thoracic aorta with endothelial and with the endothelial removed
(endothelium-denuded). Both aorta of 3 mm length were soaked into
Krebs-Henselheit solution at 37°C, pH 7.4 and aerated with carbogen gas. After
they have acclimatized, both aortas were contracted with phenylephrine
solution, after reaching peak contraction and plateau, the solution of extract
or its solvent (Control) was administered in cumulatively increasing doses. The
results show that CFS extracts induce vasorelaxation both in the
endothelial-intact aorta and in the endothelial-denuded aorta. At high
concentrations, the vasorelaxation activity in the endothelial-intact aorta was
weaker than that on endothelial-denuded aorta. This study proves that action
mechanism of blood vessels’ vasorelaxation induced by the methanol extract of
CFS were more dominantly mediated by the blood vessels smooth muscle; and at
high concentrations the endothelial actually weakened the VSMC vasorelaxation
activity. Further study is necessary on the mechanism of action vasorelaxation through the modulation
of intracellular or extracellular calcium ion channels of VSMC
Keywords: Coptosapelta
flavescens, vasorelaxation, extract, aorta, in vitro
Penulis: Sjarif Ismail, Khemasili
Kosala, Ika Fikriah, Agustina Rahayu Magdaleni
Kode Jurnal: jpfarmasidd170176
