Vaněčková I et al: Endothelin A receptor blocker atrasentan lowers blood pressure by the reduction of nifedipine-sensitive calcium influx in Ren-2 transgenic rats fed a high-salt diet. J Hypertens. 2015, 33(1): 161-9

 

Anti-obesity effects of prolactin-releasing peptide after peripheral administration

In cooperation with dr. Lenka Maletínská group from the Institute of Organic Chemistry and Biochemistry ASCR, where lipidized analogs of neuropeptide prolactin releasing peptide (PrRP) were synthesized, we studied the properties of these analogs in vitro (binding to receptors, stability in plasma, etc.) and their effect on food intake in rodents after peripheral administration. We found a very strong binding to the cells expressing PrRP receptor. Peripheral administration of palmitoylated PrRP to fasted mice led to long lasting reduction of food intake, which was associated with an increased neuronal activity in brain areas involved in the regulation of food intake. Long-term administration of analogs in obese mice resulted in decreased food intake, weight loss and normalization of some metabolic parameters. The results clearly showed that lipidized analogues of PrRP could become attractive candidates for the treatment of obesity.

Maletínská L et al: Novel lipidized analogs of prolactin-releasing peptide have prolonged half-lives and exert anti-obesity effects after peripheral administration, International Journal of Obesity. 2015, 39(6): 986-993.

 

Is calcium sensitization the key player in genetic hypertension development?

The role of alterations in Ca²⁺ sensitization (RhoA/Rho kinase pathway) and Ca²⁺ entry via voltage-gated Ca²⁺ channels were studied in developing spontaneously hypertension rats. Ca²⁺ sensitization is attenuated and Ca²⁺ entry is enhanced from prehypertensive stages. Reduced expression of upstream activators of Rho kinase and lower expression of CPI-17 (endogenous inhibitor of myosin light chain phosphatase) explain changes of Ca²⁺ sensitization during genetic hypertension development.

Behuliak M et al: Ontogenetic changes in contribution of calcium sensitization and calcium entry to blood pressure maintenance of Wistar-Kyoto and spontaneously hypertensive rats. J Hypertens. 2015; 33(12): 2443-2454.

 

The role of reactive oxygen species in salt hypertension and genetic hypertension

Enhanced production of reactive oxygen species (ROS) in the brain and/or kidney has been proposed to participate in the pathogenesis of different forms of hypertension. In our studies, we evaluated the production of superoxide radicals by plasma membrane nicotinamide-adenine dinucleotide phosphate (NADPH) oxidase in brain and kidney of hypertensive Dahl salt-sensitive rats and transgenic rats for the murine Ren-2 renin gene. We have found increased ROS production in the kidney of both hypertensive strains, whereas no changes in ROS formation were detected in the brain.

Vokurková M et al: ROS production is increased in the kidney but not in the brain of Dahl rats with salt hypertension elicited in adulthood, Physiol Res. 2015, 64: 303-312

Vokurková M et al: NADPH oxidase activity and reactive oxygen species production in brain and kidney of adult male hypertensive Ren-2 transgenic rats, Physiol Res. 2015, 64: 849-856