Activation of the α- and β-adrenergic pathways increases the
contractile velocity of adult rat cardiomyocytes cardiomyocytes.
Brian H. Crawford, AKM A. Hussain, Nathan M. Jideama
Activation of the α- and β-adrenergic signaling pathways of PKC and
PKA, respectively, of adult rat cardiomyocytes and the relative
effects on the mechanical properties of cardiomyocytes were
investigated. Isoproterenol (β-adrenergic) increased in situ
phosphorylation of troponin I more than troponin T. Phenylephrine
(α-adrenergic) and TPA (PKC activator) increased in situ
phosphorylation of TnT more than TnI. Kinetic studies revealed that
cardiomyocytic contraction velocity for the in situ phosphorylation
were 2.60×10-5m/s (control), 1.67×10-5m/s (TPA), 6.00×10-5m/s (isoproterenol),
and 3.47×10-5m/s (phenylephrine). The data suggest that contractile
velocity of cardiomyocytes increases with the phosphorylation
intensity of TnI and decreases with TnT intensity.
Gene Expression of CDK6 and
CCND1 Genes in Basal Cell Carcinoma
Sima Ataollahi Eshkoor, Patimah bt. Ismail, Sabariah Ab. Rahman
cell carcinoma (BCC) is the most common cancer among skin cancers.
Cell cycle deregulation in G1-phase is a critical event during the
course of carcinogenesis, which is probably much more important than
other phases of cell cycle, during the course of skin
carcinogenesis. CCND1 and CDK6 are important components of
regulatory pathway in arrest and uncontrolled proliferation of cell
cycle. To determine the expression pattern of CDK6, CCND1 in BCC,
this study involved ten samples of paraffin embedded of BCC tissues.
Two selected normal skin tissue were investigated using RT in situ
PCR and Immunohistochemistry (IHC) techniques. Nuclear and
cytoplasmic staining intensity of samples within tumor cells and
normal tissue illustrated a different mRNA and protein expression.
This study represents significant expression of CCND1 and CDK6 genes
in BCC (alpha level is 0.05). CDK6 and CCND1 mRNA, and protein of
these genes are expressed to induce the cell cycle proliferation and
the influence proliferation of cell cycle and BCC.