Abstract | Background: Objective: This study was designed to assess the effects of pregnancy and lactation on the vulnerability of the myocardium to an ischemic insult. Methods: Eighteen female rats were randomly divided into three groups: ischemia-reperfusion (IR), in which the hearts of virgin rats underwent IR (n = 6); lactating, in which the rats nursed their pups for 3 weeks and the maternal hearts were then submitted to IR (n = 6); and non-lactating, in which the pups were separated after birth and the maternal hearts were submitted to IR (n = 6). Outcome measures included heart rate (HR), left ventricular developed pressure (LVDP), rate pressure product (RPP), ratio of the infarct size to the area at risk (IS/AAR %), and ventricular arrhythmias - premature ventricular contraction ( PVC) and ventricular tachycardia (VT). Results: The IS/AAR was markedly decreased in the lactating group when compared with the non-lactating group (13.2 ± 2.5 versus 39.7 ± 3.5, p < 0.001) and the IR group (13.2 ± 2.5 versus 34.0 ± 4.7, p < 0.05). The evaluation of IR-induced ventricular arrhythmias indicated that the number of compound PVCs during ischemia, and the number and duration of VTs during ischemia and in the first 5 minutes of reperfusion in the non-lactating group were significantly (p < 0.05) higher than those in the lactating and IR groups. Conclusion: Lactation induced early-onset cardioprotective effects, while rats that were not allowed to nurse their pups were more susceptible to myocardial IR injury.
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Authors | Sahar Askari, Alireza Imani, Hamidreza Sadeghipour, Mahdieh Faghihi, Zohreh Edalatyzadeh, Samira Choopani, Nasser Karimi, Sulail Fatima |
Journal | Arquivos brasileiros de cardiologia
(Arq Bras Cardiol)
Vol. 108
Issue 5
Pg. 443-451
(05 2017)
ISSN: 1678-4170 [Electronic] Brazil |
PMID | 28444063
(Publication Type: Journal Article)
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Topics |
- Animals
- Arrhythmias, Cardiac
(prevention & control)
- Female
- Heart Rate
(physiology)
- Lactation
- Models, Animal
- Myocardial Contraction
(physiology)
- Myocardial Infarction
(prevention & control)
- Myocardial Ischemia
(rehabilitation)
- Myocardial Reperfusion Injury
(prevention & control)
- Pregnancy
- Random Allocation
- Rats, Sprague-Dawley
- Ventricular Pressure
(physiology)
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