Data supporting the cardiac mitochondria calcium handling in female normotensive and spontaneously hypertensive rats

In association with the published article “Mitochondrial calcium handling in normotensive and spontaneously hypertensive rats: correlation with systolic blood pressure levels” [1], this data article contains information about calcium handling of cardiac mitochondria isolated from female of both rats strains (WKY and SHR). Dataset of mitochondrial permeability transition pore (mPTP) resistance to opening Ca2+-mediated, Ca2+ retention capacity (CRC), time constants and mitochondrial membrane potential (ΔΨm) are showed.


a b s t r a c t
In association with the published article "Mitochondrial calcium handling in normotensive and spontaneously hypertensive rats: correlation with systolic blood pressure levels" [1], this data article contains information about calcium handling of cardiac mitochondria isolated from female of both rats strains (WKY and SHR). Dataset of mitochondrial permeability transition pore (mPTP) resistance to opening Ca 2 þ -mediated, Ca 2 þ retention capacity (CRC), time constants and mitochondrial membrane potential (ΔΨm) are showed.
& 2016 Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Subject area
Cardiovascular More specific subject area

Mitochondria
Type of data The data provide information about calcium handling of cardiac mitochondria obtained from female normotensive and hypertensive rats.
The data can be compared to data obtained in male rats of both strains [1]. The data can be used in the development of further experiments to analyze the influence of sex.

Data
Systolic blood pressure (SBP), body weight (BW), heart weight (HW) and hypertrophy index (HI, calculated as HW and BW ratio) of female WKY and SHR are displayed in Table 1. The mPTP resistance to opening, measured as light scattering decrease, after different Ca 2 þ concentrations in samples derived from female of both rats strains was depicted in Fig

Animal model
We used female normotensive (Wistar Kyoto, WKY) and spontaneously hypertensive rats (SHR) of 5 months of age. All procedures followed during this investigation conform to the Guide for the Care and Use of Laboratory Animals published by the US National Institutes of Health (NIH Publication no. 85-23, revised 1996) and to the guidelines laid down by the Animal Welfare Committee of La Plata School of Medicine.

Characteristics of WKY and SHR
Values of SBP, BW, HW and HI in WKY and SHR are shown in Table 1.

Isolation of rat heart mitochondria
Mitochondria were obtained by differential centrifugation following the method described by Mela and Seitz [2].

Mitochondrial permeability transition pore (mPTP) resistance to opening Ca 2 þ -mediated
The mPTP resistance to opening was assessed by addition of different Ca 2 þ concentrations to samples of 0.3 mg/mL of isolated mitochondria from hearts of WKY and SHR female. The changes were observed as decreases of light scattering and followed using a temperature-controlled Hitachi F4500 spectrofluorometer operating with continuous stirring at excitation and emission wavelengths of 520 nm [3]. Light scattering decrease (LSD) was calculated for each sample by taking the difference of scattered light between before and after the addition of CaCl 2 (Fig. 1).

Calcium retention capacity (CRC)
CRC (Fig. 2) was defined as the amount of Ca 2 þ required triggering a massive Ca 2 þ release by isolated cardiac mitochondria [4]. Briefly, successive pulses of 10 mM Ca 2 þ were added to samples of 0.3 mg/mL of isolated mitochondria of hearts from WKY and SHR. After sufficient Ca 2 þ loading, extramitochondrial Ca 2 þ concentration abruptly increased, which was recorded by fluorescence changes of Calcium green-5N with excitation and emission wavelengths set at 506 and 532 nm, respectively. Pulse time (PT, s) and exponential decay constant (EDC) of Ca 2 þ influx to mitochondria were also measured (Fig. 3).