Smooth muscle contraction mechanisms of Epicrates chencria and Boa constrictor

• Grant number: 13/04994-0
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: April 01, 2013
• End date: August 31, 2016
• Field of knowledge: Biological Sciences - Pharmacology - Autonomic Pharmacology
• Principal Investigator: Gilberto de Nucci
• Grantee: Plinio Minghin Freitas Ferreira
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 11/11828-4 - Pharmacological, eletrophysiological and morphological characterization of a novel TTX-resistant sodium channel coupled to corpus cavernosum of snakes, AP.TEM
• Associated scholarship(s): 14/04478-5 - Interactions of platelet subpopulations and their relevance to anti-platelet therapy, BE.EP.DD

Abstract

Corpora cavernosa from humans and other mammals relax to transmural stimulation, and these relaxations are sensitive to voltage-gated sodium channel blockers such as tetrodotoxin (TTX). Snakes and lizards are unique among amniote vertebrates in having a bilaterally symmetrical intromitteny penis, known as hemipenises. The transmural stimulation of Crotalus durissus terrificus hemipenises causes relaxation which is insensitive to TTX, indicating the presence of a novel sodium channel. The objective of this project is to perform a complete study of this channel, since this may offer a new insight as a potential therapeutical target for erectile dysfunction and other diseases. This will be accomplished with the following steps: Cloning of this sodium channel and expression in Xenopus oocytes to perform full electrophysiological studies. Pharmacological study using bioassay and release of 3H-noradrenaline and 3Hacetylcholine of the Crotalus durissus terrificus hemipenises. Morphological localization using transmission electron microscopy of the novel sodium channel. Screening of new toxins isolated from Conus striatus and Conus sp as potential inhibitors of this novel sodium channel. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

FERREIRA, Plinio Minghin Freitas. Soluble guanylate cyclase allosteric modulators as anti-platelet therapy: in vitro, ex vivo and in vivo studies.. 2016. Doctoral Thesis - Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI) São Paulo.