Diffusional transport of the aminoterminal propeptide of type III procollagen in the interstitium of the globally ischaemic cat myocardium

TY - JOUR

T1 - Diffusional transport of the aminoterminal propeptide of type III procollagen in the interstitium of the globally ischaemic cat myocardium

AU - Høst, N B

AU - Sejrsen, P

AU - Jensen, L T

AU - Haunsø, S

PY - 1996/11/29

Y1 - 1996/11/29

N2 - Local repair after acute myocardial infarction appears to be reflected by levels in serum of the aminoterminal propeptide of type III procollagen (serum-PIIINP). Furthermore, serum-PIIINP has recently been reported to provide information on prognosis after acute myocardial infarction. However, no attention has yet been paid to the resistance to diffusion offered by the myocardial interstitium. We determined the diffusion coefficient of PIIINP in the interstitium of the globally ischaemic interstitium of the cat (D'37) by means of a "true transient diffusion' method, and compared with the free diffusion in water (D37). D'37 (in cm2 s-1.10(-5) was 0.0157 +/- 0.0005 (mean +/- SEM) (n = 13), and D37 was 0.0624 +/- 0.0024 (n = 12). The mean diffusive progression during 20 min of the concentration profile of [125I]PIIINP into the tissue was calculated to be 0.19 mm. The D'37 of albumin is practically identical to the D'37 of PIIINP, and the myocardium offers a similar resistance to diffusion of PIIINP and albumin, as expressed from the ratio D37/D'37 of approximately 4 for both molecules. PIIINP has a molecular weight of 42,000 Da, is rod shaped and has an overall negative charge. These characteristics explain the similarity in diffusion coefficients of PIIINP and albumin, which has a molecular weight of 69,000 Da. Albumin is known to pass the membrane of the continuous capillaries of the heart, making it very likely that direct exchange of PIIINP between interstitium and capillary plasma can also occur. During one hour of interstitial diffusion PIIINP will have traversed a distance calculated tp correspond to 15-20 capillaries. Therefore, the results support the concept of serum-PIIINP as a direct marker of events taking place locally in the myocardium following acute myocardial infarction.

AB - Local repair after acute myocardial infarction appears to be reflected by levels in serum of the aminoterminal propeptide of type III procollagen (serum-PIIINP). Furthermore, serum-PIIINP has recently been reported to provide information on prognosis after acute myocardial infarction. However, no attention has yet been paid to the resistance to diffusion offered by the myocardial interstitium. We determined the diffusion coefficient of PIIINP in the interstitium of the globally ischaemic interstitium of the cat (D'37) by means of a "true transient diffusion' method, and compared with the free diffusion in water (D37). D'37 (in cm2 s-1.10(-5) was 0.0157 +/- 0.0005 (mean +/- SEM) (n = 13), and D37 was 0.0624 +/- 0.0024 (n = 12). The mean diffusive progression during 20 min of the concentration profile of [125I]PIIINP into the tissue was calculated to be 0.19 mm. The D'37 of albumin is practically identical to the D'37 of PIIINP, and the myocardium offers a similar resistance to diffusion of PIIINP and albumin, as expressed from the ratio D37/D'37 of approximately 4 for both molecules. PIIINP has a molecular weight of 42,000 Da, is rod shaped and has an overall negative charge. These characteristics explain the similarity in diffusion coefficients of PIIINP and albumin, which has a molecular weight of 69,000 Da. Albumin is known to pass the membrane of the continuous capillaries of the heart, making it very likely that direct exchange of PIIINP between interstitium and capillary plasma can also occur. During one hour of interstitial diffusion PIIINP will have traversed a distance calculated tp correspond to 15-20 capillaries. Therefore, the results support the concept of serum-PIIINP as a direct marker of events taking place locally in the myocardium following acute myocardial infarction.

KW - Animals

KW - Biological Transport

KW - Cats

KW - Chemical Phenomena

KW - Chemistry

KW - Diffusion

KW - Molecular Weight

KW - Myocardial Ischemia

KW - Myocardium

KW - Peptide Fragments

KW - Procollagen

KW - Serum Albumin

KW - Sucrose

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

M3 - Journal article

C2 - 8937761

SN - 0009-8981

VL - 255

SP - 183

EP - 194

JO - Clinica Chimica Acta

JF - Clinica Chimica Acta

IS - 2

ER -