Alteration of protein kinase C isoforms in the liver of septic rat.
The present study investigated the alteration of protein kinase C (PKC) isoforms in rat liver during the progression of sepsis. Cecal ligation and puncture (CLP) model of polymicrobial sepsis was used, with early and late sepsis referring to those animals sacrificed at 9 and 18 h, respectively, after CLP. The protein contents of various PKC isoforms were quantified by Western blot and densitometric analysis. PKCalpha activity was performed after immunoprecipitation and assayed based on the incorporation rate of 32p from [gamma-32p] adenosine triphosphate (ATP) into histone. The distribution of PKCalpha was evaluated by immunohistochemical staining. The steady state expression of PKCalpha mRNA was estimated by reverse transcriptase-polymerase chain reaction (RT-PCR). The results indicated that 1) five isoforms (alpha, beta, delta, epsilon, zeta) could be detected in normal rat liver. PKCalpha and beta were predominantly present in the cytosolic fraction, while membrane-associated PKCdelta was more prominent than that of cytosolic fraction; 2) the protein content of membrane-associated PKCalpha was significantly decreased at early (P < 0.05) and late (P < 0.01) sepsis; 3) there was no significant difference of protein contents of PKC-delta, -epsilon and -zeta between sham-operated and septic rat liver; 4) the activity of membrane-associated PKCalpha was significantly declined under detection level during sepsis; 5) at both early and late sepsis, the immunohistochemical staining of PKCalpha was significantly diminished, especially in the nucleus; 6) the RT-PCR product of PKCalpha mRNA of septic liver was significantly less than the sham-operated liver. These results suggest that inactivation and the suppression of PKC-alpha gene transcription might be involved in modulating hepatic failure during sepsis.
Hsu
Chin
C
Department of Physiology, Kaohsiung Medical University, Taiwan, ROC.
Hsieh
Ya-Ching
YC
Hsu
Hseng-Kuang
HK
Jao
Shiao-Ching
SC
Yang
Rei-Cheng
RC
D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D003600:Cytosol / Q000201:enzymology; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008099:Liver / Q000201:enzymology* / Q000473:pathology; D008297:Male; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism*; D051571:Protein Kinase C-alpha; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018805:Sepsis / Q000201:enzymology* / Q000473:pathology; D000099221:Protein Kinase C zeta
D007527:Isoenzymes; D011493:Protein Kinase C; D051571:Protein Kinase C-alpha; D012333:RNA, Messenger; D000099221:Protein Kinase C zeta