title: Reduction of pressor response to stress by centrally acting apelin in spontaneously hypertensive rats.
abstract: BACKGROUND
  Numerous studies suggest that apelin plays a significant role in cardiovascular regulation and in the pathogenesis of hypertension. The purpose of the present study was to determine whether apelin-13 (AP-13) is involved in the regulation of cardiovascular responses to acute stress in spontaneous hypertension.
  
  
  METHODS
  The effects of intracerebroventricular (ICV) administration of AP-13 on changes in mean arterial blood pressure (MABP) and heart rate evoked by an alarming stress (air jet stress) were compared in awake normotensive Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). The rats were divided into four groups: Groups 1 (WKY) and 3 (SHR) received ICV infusion of 0.9% sodium chloride (vehicle), whereas Groups 2 (WKY) and 4 (SHR) were ICV infused with AP-13. All animals were exposed to the alarming stress.
  
  
  RESULTS
  During the ICV administration of the vehicle, the pressor response to stress was significantly greater in SHR than in WKY. The ICV infusion of AP-13 reduced the pressor response evoked by the application of the stressor in SHR but not in WKY. It also abolished the difference in stress-induced MABP increases between WKY and SHR.
  
  
  CONCLUSIONS
  The results show that centrally acting apelin may play an essential role in the regulation of blood pressure responses to an alarming stress in SHR rats.
authors.forename: Ryszard Stefan
authors.initials: RS
authors.lastname: Gomolka
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Cudnoch-Jedrzejewska
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Czarzasta
authors.forename: Ewa
authors.initials: E
authors.lastname: Szczepanska-Sadowska
mesh_terms: D000818:Animals; D062186:Arterial Pressure / Q000187:drug effects*; D002319:Cardiovascular System / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006973:Hypertension / Q000503:physiopathology*; D057967:Infusions, Intraventricular; D036341:Intercellular Signaling Peptides and Proteins / Q000008:administration & dosage*; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D013312:Stress, Physiological / Q000187:drug effects*
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; C495199:apelin-13 peptide