Abstract
Centrally acting leptin induces the activation of the sympathetic nervous system with a pressor effect in normotensive rats. The purpose of the study was to examine central leptin-evoked action in critical haemorrhagic hypotension. In anaesthetized male Wistar rats subjected for irreversible haemorrhagic shock with mean arterial pressure (MAP) 20–25mmHg haemodynamic parameters and plasma concentrations of adrenaline and noradrenaline were measured. Leptin given intracerebroventricularly (20μg) evoked long-lasting rises in MAP and heart rate (HR), with a subsequent increase in renal, mesenteric and hindquarters blood flows and a 100% survival at 2h. MAP and peripheral blood flow changes were inhibited by a pre-treatment with α1- and α2-adrenoceptor antagonists prazosin (0.5mg/kg) and yohimbine (1mg/kg), while β-adrenoceptor antagonist propranolol (1mg/kg) blocked leptin-induced HR changes, without influence on MAP, peripheral blood flows and survival. Twenty min after leptin treatment, there were higher plasma concentrations of noradrenaline, but not adrenaline, in comparison with the saline-treated control group. In conclusion, centrally acting leptin induces a long-lasting pressor effect with an improvement in the survival rate in haemorrhage-shocked rats. The effect may be associated with the activation of the sympathetic nervous system.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
