Estradiol affect Na-dependent Ca2+ efflux from synaptosomal mitochondria
Apstrakt
The effects of gonadal steroid hormone, 17 beta-estradiol (E-2), in vitro on rat brain mitochondria Ca2+ movement were investigated. Intrasynaptosomal mitochondria Ca2+ uptake via an energy-driven Ca2+ uniporter have K-m = 112.73 +/- 7.3 mu mol.l(-1) and V-max = 21.97 +/- 1.7 nmol Ca-45(2+) mg(-1). Ca2+ release trough a Na+/Ca2+ antiporter was measured with a K-m for Na+ of 43.7 +/- 2.6 mmol.l(-1), and V-max of 1.5 +/- 0.3 nmol Ca-45(2+) mg(-1). Addition of estradiol in preincubation mixture did not affect the uptake of Ca2+ mediated by the ruthenium red-sensitive uniporter, while it produced biphasic effect on Na-dependent Ca2+ efflux. Estradiol at concentrations up to 1 nmol.l(-1) decreased the efflux significantly (63% inhibition with respect to the control), and at concentrations above 10 nmol.l(-1) increased it exponentially. The maximum inhibiting concentration of estradiol (0.5 nmol.l(-1)) increased the affinity of the uniporter (K-m reduced by about 30%), without affecting sign...ificantly the capacity (V-max) for Na+. The results presented suggest that estradiol inhibits Na-dependent Ca2+ efflux from mitochondria and acts on mitochondrial retention of Ca2+, which may modulate mitochondrial and consequently synaptosomal content of Ca2+, and in this way exerts its role in the homeostasis of calcium in nerve terminals.
Ključne reči:
mitochondria / Ca2+ transport / estradiol / synaptosomesIzvor:
General Physiology and Biophysics, 2000, 19, 1, 59-71Kolekcije
Institucija/grupa
VinčaTY - JOUR AU - Horvat, Anica AU - Petrović, S AU - Nedeljković, N. AU - Martinović, Jelena AU - Nikezić, Gordana S. PY - 2000 UR - https://vinar.vin.bg.ac.rs/handle/123456789/2353 AB - The effects of gonadal steroid hormone, 17 beta-estradiol (E-2), in vitro on rat brain mitochondria Ca2+ movement were investigated. Intrasynaptosomal mitochondria Ca2+ uptake via an energy-driven Ca2+ uniporter have K-m = 112.73 +/- 7.3 mu mol.l(-1) and V-max = 21.97 +/- 1.7 nmol Ca-45(2+) mg(-1). Ca2+ release trough a Na+/Ca2+ antiporter was measured with a K-m for Na+ of 43.7 +/- 2.6 mmol.l(-1), and V-max of 1.5 +/- 0.3 nmol Ca-45(2+) mg(-1). Addition of estradiol in preincubation mixture did not affect the uptake of Ca2+ mediated by the ruthenium red-sensitive uniporter, while it produced biphasic effect on Na-dependent Ca2+ efflux. Estradiol at concentrations up to 1 nmol.l(-1) decreased the efflux significantly (63% inhibition with respect to the control), and at concentrations above 10 nmol.l(-1) increased it exponentially. The maximum inhibiting concentration of estradiol (0.5 nmol.l(-1)) increased the affinity of the uniporter (K-m reduced by about 30%), without affecting significantly the capacity (V-max) for Na+. The results presented suggest that estradiol inhibits Na-dependent Ca2+ efflux from mitochondria and acts on mitochondrial retention of Ca2+, which may modulate mitochondrial and consequently synaptosomal content of Ca2+, and in this way exerts its role in the homeostasis of calcium in nerve terminals. T2 - General Physiology and Biophysics T1 - Estradiol affect Na-dependent Ca2+ efflux from synaptosomal mitochondria VL - 19 IS - 1 SP - 59 EP - 71 UR - https://hdl.handle.net/21.15107/rcub_vinar_2353 ER -
@article{ author = "Horvat, Anica and Petrović, S and Nedeljković, N. and Martinović, Jelena and Nikezić, Gordana S.", year = "2000", abstract = "The effects of gonadal steroid hormone, 17 beta-estradiol (E-2), in vitro on rat brain mitochondria Ca2+ movement were investigated. Intrasynaptosomal mitochondria Ca2+ uptake via an energy-driven Ca2+ uniporter have K-m = 112.73 +/- 7.3 mu mol.l(-1) and V-max = 21.97 +/- 1.7 nmol Ca-45(2+) mg(-1). Ca2+ release trough a Na+/Ca2+ antiporter was measured with a K-m for Na+ of 43.7 +/- 2.6 mmol.l(-1), and V-max of 1.5 +/- 0.3 nmol Ca-45(2+) mg(-1). Addition of estradiol in preincubation mixture did not affect the uptake of Ca2+ mediated by the ruthenium red-sensitive uniporter, while it produced biphasic effect on Na-dependent Ca2+ efflux. Estradiol at concentrations up to 1 nmol.l(-1) decreased the efflux significantly (63% inhibition with respect to the control), and at concentrations above 10 nmol.l(-1) increased it exponentially. The maximum inhibiting concentration of estradiol (0.5 nmol.l(-1)) increased the affinity of the uniporter (K-m reduced by about 30%), without affecting significantly the capacity (V-max) for Na+. The results presented suggest that estradiol inhibits Na-dependent Ca2+ efflux from mitochondria and acts on mitochondrial retention of Ca2+, which may modulate mitochondrial and consequently synaptosomal content of Ca2+, and in this way exerts its role in the homeostasis of calcium in nerve terminals.", journal = "General Physiology and Biophysics", title = "Estradiol affect Na-dependent Ca2+ efflux from synaptosomal mitochondria", volume = "19", number = "1", pages = "59-71", url = "https://hdl.handle.net/21.15107/rcub_vinar_2353" }
Horvat, A., Petrović, S., Nedeljković, N., Martinović, J.,& Nikezić, G. S.. (2000). Estradiol affect Na-dependent Ca2+ efflux from synaptosomal mitochondria. in General Physiology and Biophysics, 19(1), 59-71. https://hdl.handle.net/21.15107/rcub_vinar_2353
Horvat A, Petrović S, Nedeljković N, Martinović J, Nikezić GS. Estradiol affect Na-dependent Ca2+ efflux from synaptosomal mitochondria. in General Physiology and Biophysics. 2000;19(1):59-71. https://hdl.handle.net/21.15107/rcub_vinar_2353 .
Horvat, Anica, Petrović, S, Nedeljković, N., Martinović, Jelena, Nikezić, Gordana S., "Estradiol affect Na-dependent Ca2+ efflux from synaptosomal mitochondria" in General Physiology and Biophysics, 19, no. 1 (2000):59-71, https://hdl.handle.net/21.15107/rcub_vinar_2353 .