The protective effect of γ-aminobutyric acid on kidney injury induced by renal ischemia-reperfusion in ovariectomized estradiol-treated rats
Nahid Talebi1, Mehdi Nematbakhsh2, Ramesh Monajemi3, Safoora Mazaheri4, Ardeshir Talebi5, Marzieh Vafapour1
1 Water and Electrolytes Research Center, Isfahan University of Medical Sciences; Department of Biology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran
2 Water and Electrolytes Research Center; Department of Physiology, Isfahan University of Medical Sciences; IsfahanMN Institute of Basic and Applied Sciences Research, Isfahan, Iran
3 Department of Biology, Falavarjan Branch, Islamic Azad University, Isfahan, Iran
4 Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
5 Water and Electrolytes Research Center, Isfahan University of Medical Sciences; Department of Clinical Pathology, Isfahan University of Medical Sciences, Isfahan, Iran
Department of Physiology, Water and Electrolytes Research Center, Isfahan University of Medical Sciences, Isfahan
Source of Support: None, Conflict of Interest: None
Background: Renal ischemia-reperfusion injury (IRI) is one of the most important causes of kidney injury, which is possibly gender-related. This study was designed to investigate the role of g-aminobutyric acid (GABA) against IRI in ovariectomized estradiol-treated rats.
Methods: Thirty-five ovariectomized Wistar rats were used in six experimental groups. The first three groups did not subject to estradiol treatment and assigned as sham-operated, control, and GABA-treated groups. GABA (50 μmol/kg) and saline were injected in the treated and control groups 30 min before the surgery, respectively. The second three groups received the same treatments but received estradiol valerate (500 μg/kg, intramuscularly) 3 days prior to the surgery. The IRI was induced in the control and treated groups by clamping the renal artery for 45 min and then 24 h of reperfusion. All animals were sacrificed for the measurements.
Results: The serum levels of creatinine and blood urea nitrogen, kidney weight, and kidney tissue damage score significantly increased in the IRI rats (P < 0.05). GABA significantly decreased the aforementioned parameters (P < 0.05). The uterus weight increased significantly in rats that received estradiol (P < 0.05). Serum and kidney levels of nitrite (nitric oxide metabolite) did not alter significantly. Serum level of malondialdehyde increased significantly in the ovariectomized rats exposed to IRI (P < 0.05).
Conclusions: It seems that GABA improved IRI in ovariectomized rats. Estradiol was also nephroprotective against IRI. However, co-administration of estradiol and GABA could not protect the kidney against IRI.