Revista Brasileira de Farmacognosia
Print version ISSN 0102-695X
RODRIGUEZ, Vania et al. Effects of a cyanobacterial extract containing-anatoxin-a(s) on the cardiac rhythm of Leurolestes circunvagans. Rev. bras. farmacogn. [online]. 2012, vol.22, n.4, pp.775-781. Epub May 29, 2012. ISSN 0102-695X. http://dx.doi.org/10.1590/S0102-695X2012005000073.
This work presents the effects of an anatoxin-a(s)-containing extract on a cockroach semi-isolated heart preparation and the results supporting the extract’s biological activity on acetylcholinesterase (purified from ell). The presence of the toxin in cyanobacterial strains Anabaena spiroides (ITEP-024, ITEP-025 and ITEP-026) isolated from the Tapacurá reservoir in Pernambuco, Brazil, was confirmed by means of liquid chromatography coupled to an ion-trap mass spectrometer. The anticholinesterase activity was assessed biochemically by the Ellman test and was confirmed by measuring the cockroach’s heart rate. The concentration of the extract containing the tested anatoxin-a(s) (antx-a(s)) (10, 16 and 100 μg.μL-1) inhibited the eel acetylcholinesterase (AChE) by more than 90%. The cockroach cardiac frequency increased by a maximum of about 20% within 29 min after the addition of 2.5x103 μg of extract containing antxa (s).g-1 bw (n=9, p<0.05). Our results strongly indicate that antx-a(s) is capable of exerting biological effects on cockroach, indicating that more research might be conducted to determine its role in the environment, especially on insects.
Keywords : Anatoxin-a(s); anticholinesterasic agents; Anabaena spiroides; cyanotoxins; cockroach.