Cardiac autonomic control in pre and postprandial situation in the Nile Tilapia, Oreochromis niloticus

• Grant number: 17/01616-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2017
• End date: November 30, 2018
• Field of knowledge: Biological Sciences - Zoology - Physiology of Recent Groups
• Principal Investigator: Luiz Henrique Florindo
• Grantee: Igor Noll Guagnoni
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil

Abstract

Nutrition requires a series of physiological adjustments in order to accomplish the energy demands of organisms. One of these adjustments, commonly referred to as Specific Dynamic Action (SDA), an increase in heart rate and cardiac output of animals to supply the increased demand related to aerobic digestion-which derives mainly from the gastrointestinal system stands out. Thus, cardiovascular adjustments are necessary to the systemic modulation of the organism as, for example, increase in heart rate (fH) and at the cardiac output (QC). In most ectotherms studied so far, postprandial tachycardia is triggered by the reduction in vagal tone in combination with non-adrenergic non-cholinergic (NANC) factors. However, such adjustments studied in a single species of teleost fish, Dicentrarchus labrax, showed only the involvement of the cholinergic tone reduction, not displaying the action of NANC factors. As the modulation of postprandial tachycardia in teleost fishes was investigated only in a single species, it is evident that there is a gap in this physiological knowledge within the group of vertebrates. In this context, using as an experimental model the Nile Tilapia (Oreochromis niloticus), this proposal aims to calculate the cardiac autonomic tone of the post during fasting and after feeding, to check what is the influence of autonomic nervous system on the heart in these situations, to investigate what is the influence of the autonomic nervous system in the modulation of postprandial tachycardia in this species, as well as checking if there is influence of NANC factors in the modulation of this adjustment, continuing investigations of cardiac postprandial modulation in teleosts. In order to do this, the animals are separated into two groups, in which both will go through a process of prolonged fasting of 96 hours prior to exploitation. However, one of the groups will be fed to satiation before the process of exploitation. From there, the animals will be instrumented with subdermal needle electrodes, oral and intraperitoneal cannula (drugs administration) in order to register fH, ventilatory amplitude (VAMP) and respiratory rate (fR). The data will be collected in three phases with periods of 1 hour each: initially with non-treated animals, later the cholinergic muscarinic antagonist (atropine) administration, and, after the establishment of a double block cardiac autonomic, with atropine and propranolol (beta-adrenergic antagonist). (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GUAGNONI, IGOR NOLL; ARMELIN, VINICIUS ARAUJO; DA SILVA BRAGA, VICTOR HUGO; RANTIN, FRANCISCO TADEU; FLORINDO, LUIZ HENRIQUE. Postprandial cardiorespiratory responses and the regulation of digestion-associated tachycardia in Nile tilapia (Oreochromis niloticus). JOURNAL OF COMPARATIVE PHYSIOLOGY B-BIOCHEMICAL SYSTEMIC AND ENVIRONMENTAL, v. 191, n. 1, p. 55-67, JAN 2021. (17/01616-6, 08/57712-4)