title: Comparison Of Cardiovascular Characteristics In Normotensive And Hypertensive Rat Strains.
abstract: BACKGROUND
  Hypertensive rats serve as valuable tools for studies of dysregulations in cardiovascular functions before and during pathological elevation of blood pressure. They exhibit many defects in structure and function of heart and vessels which are often related to severity of hypertension.
  
  
  OBJECTIVE
  The relationship of blood pressure level and manifestation of aberrations in selected cardiovascular and metabolic parameters were determined in 20-week-old normotensive Wistar-Kyoto (WKY) rats, spontaneously hypertensive rats (SHR) and in their F1 offspring borderline hypertensive rats (BHR), and also in normotensive Wistar rats which are genetically less compatible with the other mentioned rat strains.
  
  
  METHODS
  Systolic blood pressure and heart rate were measured in conscious rats by the non-invasive tail-cuff method. At the end of the treatment, rats were sacrificed, relative weight of their left heart ventricle and liver were determined and plasma concentration of glucose and triglycerides were measured. Thoracic aorta and superior mesenteric artery were isolated and prepared for isometric tension recording. Neurogenic contractions were elicited by electrical stimulation of perivascular adrenergic nerves.
  
  
  RESULTS
  The level of systolic blood pressure in WKY rats (106.0 ± 0.4 mmHg), BHR (149.5 ± 2.5 mmHg) and SHR (186.4 ± 3.9 mmHg) corresponded with the impairment of acetylcholine-induced relaxation of isolated thoracic aorta and with the increase in sensitivity of contractile responses to exogenous noradrenaline and to electrical stimulation of perivascular adrenergic nerves in mesenteric artery. However, rats of the normotensive strain Wistar (118.1 ± 2.0 mmHg) exhibited arterial contractions similar to those obtained in hypertensive rats. Wistar rats had also the highest relative liver weight and plasma triglyceride concentration.
  
  
  CONCLUSIONS
  These observations indicate that when comparing non-related rat strains the higher magnitude of arterial contractions and abnormal lipid parameters may not correlate with hypertensive state.
authors.forename: Anna
authors.initials: A
authors.lastname: Zemancíková
authors.forename: Jozef
authors.initials: J
authors.lastname: Török
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000294:innervation; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure / Q000235:genetics; D002319:Cardiovascular System / Q000503:physiopathology*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D005838:Genotype; D006339:Heart Rate; D006973:Hypertension / Q000097:blood / Q000235:genetics / Q000503:physiopathology*; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects / Q000294:innervation; D010641:Phenotype; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D013045:Species Specificity; D014280:Triglycerides / Q000097:blood; D014661:Vasoconstriction; D014662:Vasoconstrictor Agents / Q000494:pharmacology; D014664:Vasodilation; D014665:Vasodilator Agents / Q000494:pharmacology
chemical_list: D001786:Blood Glucose; D014280:Triglycerides; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents