Malnutrition alters the cardiovascular responses induced by central injection of tityustoxin in Fischer rats.
Scorpion envenoming and malnutrition are considered two important public health problems in Brazil, involving mainly children. Both these conditions are more common among the economically stratified lower income portion of the population, thus suggesting that these factors should be analyzed concomitantly. It is known that cardiorespiratory manifestations, as cardiac arrhythmias, arterial hypertension and hypotension, pulmonary edema and circulatory failure are the main "causa mortis" of scorpion envenomation. Additionally, there are evidences in the literature that deficiencies in dietary intake endanger the CNS and modify the cardiovascular homeostasis. Then, the objective of this work is to evaluate the protein malnourished effect on cardiovascular responses induced by tityustoxin (TsTX, an α-type toxin extracted from the Tityus serrulatus scorpion venom). Fischer rats (n = 20) were injected i.c.v. with TsTX and divided in control and malnorished groups, which were, respectively, submitted to a control and a low-protein diet. Arterial pressure recordings were done until death of the animals. Although both groups presented an increased mean arterial pressure after TsTX injection, this increase was smaller and delayed in malnourished rats, when compared to control rats. In addition, heart rate increased only in rats from the control group. Finally, malnourished rats had an increase in survival time (9:9/13.5 vs. 15.5:10.5/18 min; p = 0.0009). In summary, our results suggest that the protein restriction attenuates the cardiovascular manifestations resulting from TsTX action on CNS.
Laboratório de Fisiologia Cardiovascular, Departamento de Ciências Biológicas, Instituto de Ciências Biológicas, Universidade Federal de Ouro Preto, Morro do Cruzeiro, 35400000 Ouro Preto, Minas Gerais, Brazil; Programa de Pós-graduação em Ciências Biológicas - NUPEB, Universidade Federal de Ouro Preto, Campus Universitário, Morro do Cruzeiro, 35400000 Ouro Preto, Minas Gerais, Brazil.
Fernanda Cacilda Santos
FC
Silva
Patrícia Alves
PA
Guidine
Mara Fernandes
MF
Ribeiro
Luciano Gonçalves
LG
Fernandes
Carlos Henrique
CH
Xavier
Rodrigo Cunha
RC
de Menezes
Marcelo Eustáquio
ME
Silva
Tasso
T
Moraes-Santos
Márcio Flávio
MF
Moraes
Deoclécio Alves
DA
Chianca
D000818:Animals; D062186:Arterial Pressure / Q000187:drug effects; D002319:Cardiovascular System / Q000187:drug effects*; D018753:Diet, Protein-Restricted; D006706:Homeostasis; D008297:Male; D044342:Malnutrition / Q000150:complications* / Q000503:physiopathology; D009498:Neurotoxins / Q000633:toxicity*; D051381:Rats; D011916:Rats, Inbred F344; D065008:Scorpion Stings / Q000150:complications* / Q000503:physiopathology; D012604:Scorpion Venoms / Q000633:toxicity*
D009498:Neurotoxins; D012604:Scorpion Venoms; C003609:tityustoxin
Cardiovascular responses; Malnutrition; Scorpion envenomation; Tityustoxin