The link between deficiency of endocrine system and cardiovascular pathology has not been completely elucidated. Aim: To induce cardiac hypertrophy with Isoproterenol (ISO) and see the effect on coronary flow (C.F). and LVPD, and to evaluate the redox potential during ischemia and hypertrophy estimating GGT,GSTand the level of Thyol groups and to see the effects of treatment with Testosterone (T),Hydrocortisone (Hy),estradiol (Es) associated with ISO on cardiovascular system in rats of different genders.
Design and method:
40 Wistar rats aged 8 months old:20 male and 20 female were divided into 4 groups of 10 rats each (5male and 5 female):A Controls treated with 0.9% saline, B treated for 20 days with ISO i.m. injections for induction of cardiac hypertrophy,C treated with Hy 1,8 mg/kg,D male treated withT 6,75 mg/kg, female treated with Es 0,45 mg/kg. From 8th day of treatment, rats received also treatment with ISO (0.5 mg/kg. C.F. and LVDP were determined in isolated perfused rat hearts mounted in Langendorff retrograde perfussion system for all groups. Cardiac hypertrophy has been evaluated using the hypertrophy index: myocardial weight/body weight, left ventricle weight/ b.w. GGT, GST and Thyol groups have been evaluated from left ventricle using standard biochemical techniques.
A 50% reduction in C.F in ISO treated rats was recorded and LVDP was depressed in the beginning and then was gradually increased. Protection of myocardium against oxidative stress was significantly depressed following ISO treatment, synthesis and utilization of GSH was limited versus controls. There was an increase in GGT in ISO treated male versus Controls. Hy administration lead to a decrease of GGT activity while in female Es lead to amplification of activity both for Controls and ISO treated. ISO treated female presented an increase in Thyol groups,the association with Es treatment lead to a decrease. ISO treated male or associated with T treatment manifested an increase in Thyol groups.
ISO treatment in rats induced cardiac hypertrophy and changes in physiological parameters of heart with a negative impact upon synthesis of antioxidant enzymes. Myocardial insufficiency exhibits biochemical particularities related to gender and etiological factors. Our data may have a clinical significance.