PMID- 10972529
OWN - NLM
STAT- MEDLINE
DCOM- 20001214
LR  - 20190826
IS  - 0305-1870 (Print)
IS  - 0305-1870 (Linking)
VI  - 27
IP  - 9
DP  - 2000 Sep
TI  - Impaired heart function and noradrenaline release after ischaemia in stroke-prone 
      spontaneously hypertensive rats.
PG  - 664-70
AB  - 1. Stroke-prone spontaneously hypertensive rats (SHRSP) are a strain of rat that 
      exhibit severely high blood pressure and stroke attacks at an early age, but 
      their heart function in vitro has seldom been studied in detail. Although the 
      activity of the sympathetic nervous system is known to increase after myocardial 
      ischaemia, there is little information about the cardiac release of noradrenaline 
      (NA) associated with heart function after ischaemia in SHRSP. The aim of the 
      present study was to examine heart function and cardiac NA release after 
      ischaemia in SHRSP. 2. Isolated hearts of 4- and 8-month-old SHRSP and 
      age-matched Wistar-Kyoto (WKY) rats were perfused in a working heart preparation 
      and were subjected to 30 min ischaemia followed by 30 min reperfusion. Heart 
      function and coronary flow were monitored throughout the experiment. Coronary 
      effluent was collected for determination of NA using high-performance liquid 
      chromatography coupled with electrochemical detection. 3. Under baseline 
      conditions, cardiac output of 4-month-old SHRSP was slightly but significantly 
      decreased compared with that of WKY rats (P < 0.05), although coronary flow was 
      maintained normally at this age. Eight-month-old SHRSP showed a further 
      impairment of systolic heart function, with lower coronary flow and higher 
      coronary vascular resistance under baseline conditions. Elevated left ventricular 
      end-diastolic pressure was evident in SHRSP at both ages before ischaemia. Heart 
      function was severely damaged after 30 min global ischaemia in SHRSP from both 
      age groups. Stroke-prone spontaneously hypertensive rats also showed lower 
      coronary flow and higher coronary vascular resistance during reperfusion. 4. 
      Coronary NA was not detectable in WKY rats or SHRSP at 4 months of age under 
      baseline conditions. In 8-month-old SHRSP, pre-ischaemic NA release was 
      significantly higher than that in age-matched WKY rat controls. The concentration 
      of NA in the coronary effluent of SHRSP during reperfusion was also significantly 
      higher than that of WKY rats at both ages. 5. These data demonstrate that SHRSP 
      have early impairment of both systolic and diastolic heart function compared with 
      WKY rats. Severe damage of heart function and coronary flow after ischaemia in 
      SHRSP was accompanied with an increased release of NA, which may play a harmful 
      role in heart function impairment in SHRSP after ischaemia.
FAU - Chen, H
AU  - Chen H
AD  - Department of Pharmacology, Kinki University School of Medicine, Osaka, Japan. 
      hchen100@hotmail.com
FAU - Azuma, M
AU  - Azuma M
FAU - Maeda, K
AU  - Maeda K
FAU - Kajimoto, N
AU  - Kajimoto N
FAU - Higashino, H
AU  - Higashino H
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Australia
TA  - Clin Exp Pharmacol Physiol
JT  - Clinical and experimental pharmacology & physiology
JID - 0425076
RN  - X4W3ENH1CV (Norepinephrine)
SB  - IM
MH  - Animals
MH  - Blood Pressure/physiology
MH  - Body Weight/physiology
MH  - Coronary Circulation/physiology
MH  - Heart/anatomy & histology/*physiopathology
MH  - Heart Rate/physiology
MH  - Male
MH  - Myocardial Ischemia/*physiopathology
MH  - Myocardial Reperfusion
MH  - Myocardium/*metabolism
MH  - Norepinephrine/*metabolism
MH  - Organ Size/physiology
MH  - Rats
MH  - Rats, Inbred SHR
MH  - Rats, Inbred WKY
MH  - Vascular Resistance/physiology
MH  - Ventricular Dysfunction, Left/etiology
MH  - Ventricular Pressure
EDAT- 2000/09/06 11:00
MHDA- 2001/02/28 10:01
CRDT- 2000/09/06 11:00
PHST- 2000/09/06 11:00 [pubmed]
PHST- 2001/02/28 10:01 [medline]
PHST- 2000/09/06 11:00 [entrez]
AID - 10.1046/j.1440-1681.2000.03325.x [doi]
PST - ppublish
SO  - Clin Exp Pharmacol Physiol. 2000 Sep;27(9):664-70. doi: 
      10.1046/j.1440-1681.2000.03325.x.