Chronic Angiotensin II (AngII) – Induced Hypertension is Attenuated by Overexpression of Copper/Zinc Superoxide Dismutase in the Median Preoptic Nucleus | Chapter 08 | New Horizons in Medicine and Medical Research Vol. 9

 Angiotensin II (AngII) can reach the brain through circumventricular organs (CVOs), such as the subfornical organ (SFO) and the organum vasculosum of the lamina terminalis, to control blood pressure (OVLT). We wanted to see if elevated amounts of superoxide in the OVLT play a role in AngII's hypertensive effects. To allow superoxide dismutase overexpression, adenoviral vectors carrying human copper/zinc superoxide dismutase (CuZnSOD) or control adenovirus (AdEmpty) were injected directly into the OVLT of rats. Rats were administered AngII (10 ng/kg/min) intravenously for ten days after three days of saline infusion. After 10 days, AdEmpty rats (n = 6) had a blood pressure rise of 33 8 mmHg, whereas rats overexpressing CuZnSOD (n = 8) in the OVLT had a blood pressure increase of just 18 5 mmHg Infusion of AngII. These findings back up the idea that excessive OVLT production plays a role in the development of persistent AngII-dependent hypertension. The brain is thought to perceive circulating angiotensin II (AngII) levels through circumventricular organs like the subfornical organ (SFO) and adjust sympathetic nervous system output accordingly. However, the cellular signalling pathways involved in these interactions remain unclear. We investigated if an underlying mechanism in the long-term hypertensive consequences of chronic AngII is overproduction of intracellular superoxide in the median preoptic nucleus (MnPO). Adenoviral vectors carrying human CuZnSOD (AdCuZnSOD) or a control vector (AdEmpty) were directly injected into the MnPO of rats equipped with aorta telemetric transmitters for arterial pressure measurement. Rats were administered AngII (10 ng/kg/min) intravenously for ten days after a three-day saline infusion control period. In the MnPO, rats overexpressing CuZnSOD (n = 7) had after ten days of AngII infusion, blood pressure increased only 6 2 mmHg, but blood pressure increased 21 4 mmHg in AdEmpty-infected rats (n = 9). These results support the idea that MnPO production contributes to the development of chronic AngII-dependent hypertension.

Author(S) Details

John P. Collister
Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.

Mitch Bellrichard
Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.

Donna Drebes
Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.

David Nahey
Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.

Jun Tian
Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE 68198, USA.

Matthew C. Zimmerman
Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE 68198, USA.

View Book:- https://stm.bookpi.org/NHMMR-V9/article/view/6903

Overexpression of Copper/Zinc Superoxide Dismutase in the Organum Vasculosum of the Lamina Terminalis (OVLT) Attenuates Chronic Angiotensin II-Induced Hypertension in the Rat | Chapter 07 | New Horizons in Medicine and Medical Research Vol. 9

 Angiotensin II (AngII) can reach the brain through circumventricular organs (CVOs), such as the subfornical organ (SFO) and the organum vasculosum of the lamina terminalis, to control blood pressure (OVLT). We wanted to see if elevated amounts of superoxide in the OVLT play a role in AngII's hypertensive effects. To allow superoxide dismutase overexpression, adenoviral vectors carrying human copper/zinc superoxide dismutase (CuZnSOD) or control adenovirus (AdEmpty) were injected directly into the OVLT of rats. Rats were administered AngII (10 ng/kg/min) intravenously for ten days after three days of saline infusion. After 10 days, AdEmpty rats (n = 6) had a blood pressure rise of 33 8 mmHg, whereas rats overexpressing CuZnSOD (n = 8) in the OVLT had a blood pressure increase of just 18 5 mmHg Infusion of AngII. These findings back up the idea that excessive OVLT production plays a role in the development of persistent AngII-dependent hypertension.

Author(S) Details

John P. Collister
Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.

Heather Taylor-Smith
Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.

Donna Drebes
Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.

David Nahey
Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, MN 55108, USA.

Jun Tian
Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE 68198, USA.

Matthew C. Zimmerman
Department of Cellular and Integrative Physiology, University of Nebraska Medical Center, Omaha, NE 68198, USA.

View Book:- https://stm.bookpi.org/NHMMR-V9/article/view/6902

Determination of Atrazine/Streptozotocin-Induced Oxidative Stress and Mitigating Effect of Virgin Coconut Oil in Male Wistar Rats | Chapter 08 | Current Aspects in Pharmaceutical Research and Development Vol. 7

 The goal of this study is to see if Virgin Coconut Oil (VCO) can help rats recover from atrazine-induced metabolic disruption. Adult male albino wistar rats weighing 180-200g were used in the study. They were randomly assigned to one of two primary experimental groups (The test and recovery groups). In the test group, 35 rats were randomly divided into five sub-groups of seven rats each (n=7) and treated as follows: Subgroup (SG) 1 was the normal control, receiving 10 ml/kg of distilled water, SG 2 received 10 ml/kg of VCO, SG 3 received 123 mg/kg of Atrazine (ATZ), SG 4 was the diabetes control that was left untreated, and SG 5 was the diabetic group that received 10 ml/kg of VCO. The animals in the test group were given medication for two weeks before being slaughtered and blood taken for examination. Thirty-five rats from the recovery group were divided into five sub-groups of seven rats each (n=7) and treated as follows for these two weeks: The control group received 10 ml/kg of distilled water, while SG 2 received 10 ml/kg of VCO and SG 3, 4, and 5 received 123 mg/kg of ATZ. The animals were re-treated for recovery after 2 weeks as follows: SG 1 received 10ml/kg distilled water, SG 2 received 10ml/kg VCO, SG 3 received 123mg/kg ATZ, SG 4 received 10ml/kg VCO, and SG 5 received 10ml/kg of distilled water. The animals were slaughtered after two weeks, and their blood was collected for study. Gluthatione (GSH), Superoxide Dismutase (SOD), and Catalase (CAT) levels were considerably lower (p0.05) in the atrazine and diabetes groups as compared to the normal control. GSH levels in the VCO recovery group were substantially higher (p0.05) than in the ATZ group after recovery. Finally, ATZ poisoning generated oxidative stress, but its withdrawal lowered stress considerably, with a stronger impact after VCO delivery.

Author(S) Details

Olatunbosun Titilope Helen
Department of Physiology, University of Uyo, P.M.B. 1017, Uyo, Akwa Ibom State, Nigeria.

Uka Emmanuel
Department of Biochemistry, University of Uyo, P.M.B. 1017, Uyo, Akwa Ibom State, Nigeria.

Asuquo Etim Asuquo
Department of Physiology, University of Uyo, P.M.B. 1017, Uyo, Akwa Ibom State, Nigeria.

Jessica David Utibe
Department of Physiology, University of Uyo, P.M.B. 1017, Uyo, Akwa Ibom State, Nigeria.

Otanwa Oladunni Omolabake
Department of Biochemistry, University of Uyo, P.M.B. 1017, Uyo, Akwa Ibom State, Nigeria.

Akwo-Nelson Violet
Department of Biochemistry, University of Uyo, P.M.B. 1017, Uyo, Akwa Ibom State, Nigeria.

View Book:- https://stm.bookpi.org/CAPRD-V7/article/view/5417