心肌缺血预处理精品PPT教学课件

Several possibilities have been suggested including:
•adenosine activation;
•preservation of high-energy phosphates;
•washout of metabolites;
•rol20e20o/12f/6Ca++-channels;
E DP (m mH g)
100
Control CPC 80
60
40
20
0
0
20
40
60
80
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Duration of Ischemia (min)
9
BIOCHEMISTRY
• Biochemical parameters of the heart tissue: a similar protection was observed for ATP, energy charge, ascorbate and other parameters.
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3
The System: Isolated rat heart The procedure : Three episodes of 2’ global ischemia separated by 3’ reperfusion
PC
Stabilization Pc R Pc R Pc R
COPPER AND FREE RADICALS IN ISCHEMIA AND
OBTAINED INDICATIONS FOR THEIR
I2N02V0/1O2/6LVEMENT IN CARDIAC PC
10 min
1 12 23 3
Reperfusion
20 min
Ischemia
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4
Two windows of protection by ischemic PC have been identified: 1 – 3 hours following PC, and 24
hour following PC.
12
•increase in antioxidants activity; •synthesis of heat-shock proteins, G-proteins; •nitric oxide production; •role of K+-channels; •role of PKC
•WE HAVE BEEN STUDYING THE ROLES OF IRON,
We work with the isolated rat heart, and will focus on the first
window.
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5
Cardiac Function without and with PC has been studied. Below the following parameters are presented:
• in the coronary flow: leakage into the CF of cellular metabolites:
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10
HPLC Analysis of the First 10-CFFs Following 35’ Global Ischemia PC
70 60 50 40 30 20 10 SA
EARLY SIGNALING PATHWAY IN HEART PROTECTION BY ISCHEMIC PRECONDITIOc preconditioning (PC) is the phenomenon describing protection of the heart against reperfusion injury following prolonged ischemia, by virtue of prior short episode (or episodes) of ischemia and reperfusion.
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2
An analogous phenomenon of cardiac protection against reperfusion injury by pre-administration of a drug is called drug-induced PC.
We have developed a family of drugs that can do it.
DP = PSP - EDP
+dP/dt
EDP
other parameters not shown
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6
Developed Pressure (DP) (% of pre-ischemic value) Versus Ischemic Time ± Preconditioning (PC)
0
2020/12/6
SP
Ino AA
UA
Control: ischemia of 35’- no PC Preconditioning fo11llowed by 35’ ischemia
Currently Proposed Mechanisms of Protection by PC
The detailed understanding of the mechanism of PC is still under investigation.
+ d P /d t (r eco ve ry % )
120
100
80 60
40
20
0 0
2020/12/6
Control CPC
20
40
60
80
Duration of Ischemia (min)
8
EDP (mmHg) Versus Ischemic Time ±Preconditioning (CPC)
D ev.Pressur e (recov ery % )
120
100
80
60
40
20
0 0
2020/12/6
Control CPC
20
40
60
80
7
Duration Ischemia (min)
+dP/dt (%) Versus Ischemic Time ±Preconditioning (CPC)