Premium
Coping with acute hypertensive stressors after selective carotid body ablation in conscious spontaneously hypertensive rats (873.10)
Author(s) -
Pijacka Wioletta,
McBryde Fiona,
Paton Julian
Publication year - 2014
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.28.1_supplement.873.10
Subject(s) - medicine , carotid body , carotid sinus , hypoxia (environmental) , baroreceptor , heart rate , cardiology , blood pressure , basal (medicine) , denervation , anesthesia , endocrinology , carotid arteries , oxygen , chemistry , organic chemistry , insulin
We have previously shown that bilateral carotid sinus denervation in SHR reduces arterial pressure (AP). This technique, however, also removes carotid sinus baroreceptors. We hypothesized that the fall in basal AP with selective bilateral CBA would not impair the normal cardiovascular responses to hypoxia, exercise and restraint stress. SHR were implanted with telemetry devices to record AP, and responses to hypoxia (10% O 2 ), exercise (10m/min) and restraint stress were tested. The chemoreflex was tested with i.v. sodium cyanide (120μg.kg ‐1 ); this response was abolished after CBA (n=4) but preserved in Shams (n=3). Basal systolic AP fell significantly after 14 days in CBA (‐18.2±2mmHg) compare to Sham (2.5±0.6mmHg), (P<0.05). SHR with CBA showed a depressor effect to 10% oxygen (‐15.3±7mmHg) whereas a pressor response was seen in Sham (15.9±6mmHg; P<0.029); heart and respiratory rates were not different. The change in AP was similar between groups during both exercise (CBA 12±7 vs. Sham 23±8mmHg, respectively; NS) and restraint stress (CBA 28±8 vs. Sham 17±9mmHg; NS). We conclude that chronic CBA prevents the pressor response to hypoxia but does not affect cardiovascular adjustment to exercise and restraint stress. Grant Funding Source : Supported by the British Heart Foundation and Cibiem