Piet Borgdorff

Learn More
The aims of this study were (a) to apply in the animal with intact baroreflex a two-point method for estimation of overall, effective open-loop gain, G0e, which results from the combined action of baroregulation and total systemic autoregulation on peripheral resistance; (b) to predict specific baroreflex gain by correcting the effective gain for the(More)
Regular fluctuations in pupil size of the cat were measured and the properties, nervous pathways, and origin of these oscillations were investigated. The rhythm of pupil movements under control conditions appeared to be either locked to the central respiratory cycle or to the artificial ventilatory cycle. These movements were only seen in lightly(More)
BACKGROUND Migraine patients are at an increased risk for stroke, as well as other thromboembolic events. This warrants further study of the role of platelets in a proportion of migraine patients. OBJECTIVE To extend the "platelet hypothesis" using literature data and observations made in a rat model of shear stress-induced platelet aggregation. Such(More)
OBJECTIVES We aimed to investigate the effect of parecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, on in vivo shear stress-induced platelet aggregation in a rat model of arterial bypass with focal narrowing. BACKGROUND Long-term use of COX-2 inhibitors is associated with increased incidence of adverse cardiovascular events, especially in patients(More)
BACKGROUND Cardiopulmonary bypass and hemodialysis often cause hypotension. We investigated a possible role of pump-induced platelet activation with consequent serotonin release. METHODS AND RESULTS In rats, a heparin-coated extracorporeal shunt was placed between the proximal part of a carotid artery and the distal part of a femoral artery. Autoperfusion(More)
Studying genetic determinants of intermediate phenotypes is a powerful tool to increase our understanding of genotype-phenotype correlations. Metabolic traits pertinent to the central nervous system (CNS) constitute a potentially informative target for genetic studies of intermediate phenotypes as their genetic underpinnings may elucidate etiological(More)
The influence of pump perfusion on autoregulation was studied in the hindleg of the halothane- and chloralose-anesthetized cat. Flow was measured with an electromagnetic flow probe in a tube between aorta and the vascularly isolated, denervated leg and varied with a calibrated occluder. Perfusion pressure was measured via a T-piece distal to the occluder.(More)
BACKGROUND The sum of undesirable side effects, occurring during haemodialysis (HD), is called bio-incompatibility. Concerning platelets, both an increase in the expression of the cell surface marker P-selectin (CD62p) and release of the intracellular granule product platelet factor 4 (PF4) have been described. However, as PF4 is also abundantly present on(More)
The interaction between autoregulation and baroregulation and its effect on the gains of the short-term pressure regulatory system was studied by performing both open- and closed-loop experiments in the same five anesthetized, vagotomized dogs, and by analyzing the data making use of a new model. With carotid pressure constant (no baroregulation) the(More)