spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

Right arrow Help viewing high resolution images
Right arrow Return to article
(Downloading may take up to 30 seconds.
If the slide opens in your browser, select File -> Save As to save it.)
Click on image to view larger version.


Figure 2


Fig. 2. Structure of ventricular, atrial and neonatal rat cardiac myocytes. Panels A, B and C depict immunostained adult ventricular, adult atrial and neonatal ventricular myocytes respectively. The left-hand panels (Ai, Bi and Ci) show cells immunostained with a monoclonal antibody raised against {alpha}-actinin (Sigma). The middle panels (Aii, Bii and Cii) display cells immunostained with a polyclonal antibody raised against type 2 RyRs (a kind gift from Prof. V. Sorrentino, San Raffaele Scientific Institute, Siena, Italy). The right-hand panels (Aiii, Biii and Ciii) depict cells immunostained with a monoclonal antibody raised against the type 1 sodium/calcium exchanger (R3F1; a kind gift from Prof. K. Philipson, UCLA, California). To visualise the NCX staining in the neonatal myocytes, a field of confluent cells is depicted (Ciii) because this provides the best contrast in these flat cells. The neonatal myocyte nuclei were visualised by DAPI staining (pseudocoloured in blue). Specific immunostaining was visualised using secondary antibodies conjugated to Alexa Fluor 405 (blue), 488 (green) or 568 (red). The {alpha}-actinin staining shows the precise striated structure of the fully differentiated adult ventricular and atrial cells (Ai and Bi). The neonatal cells show {alpha}-actinin striation (Ci), but they do not have the same degree of organisation as their adult counterparts. RyRs have a regular transverse striated pattern in adult cells (Aii and Bii). Note the two distinct populations of RyRs in adult atrial cells. In addition to the transverse `non-junctional' RyRs, atrial cells express a ring of `junctional' RyRs (Bii). The latter are responsible for the initiation of EC coupling around the circumference of the cell. In the neonatal myocytes (Ci), the degree of RyR expression is lower and these are less organised than in adult cells. In both atrial (Biii) and neonatal cells (Ciii), the NCX staining is prominent only around the circumference of the cells. In ventricular myocytes that have T-tubules, the NCX protein is evident on the sarcolemma and at the Z-lines deep inside the cells (Aiii). Bars, 20 µm.





Right arrow Return to article