Comparison of myocardial ischemic/hypoxic staining techniques for evaluating the alleviation of exhaustive exercise-induced myocardial injury by exercise preconditioning.

Exercise preconditioning (EP) can alleviate myocardial ischemic/hypoxic injury by inducing endogenous cardioprotection. Hematoxylin-eosin (HE), hematoxylin-basic fuchsin-picric acid (HBFP), and chromotrope-2R brilliant green (C-2R BG) staining have been used to visualize myocardial ischemic/hypoxic changes in previous EP studies, but comprehensive evaluation and comparisons of these methods are lacking. This study evaluated ischemic/hypoxic changes in adjacent myocardial sections by HE, HBFP, and C-2R BG and compared the characteristics of sections stained by these three methods to show changes associated with exercise-induced myocardial ischemic/hypoxic injury. Rats were randomly divided into four groups: control (C), exercise preconditioning (EP), exhaustive exercise (EE), and exercise preconditioning + exhaustive exercise (EP + EE). Adjacent myocardial sections were stained as described above and compared to evaluate the effects of exercise-induced myocardial ischemic/hypoxic injury. The three staining methods revealed consistent localization patterns of myocardial ischemic/hypoxic injury in all groups. Results suggest that EP can alleviate exhaustive exercise-induced myocardial ischemic/hypoxic injury, and the three staining methods are suitable for the histological study of exercise-induced myocardial ischemic/hypoxic injury and protection. HE staining is a simple procedure but is not specific for myocardial ischemic/hypoxic injury. HBFP and C-2R BG staining can be used to specifically visualize myocardial ischemic/hypoxic injury.

COEXISTENCE OF CORTICOTROPIN RELEASING FACTOR AND NEUROTENSIN IN THE OVAL NUCLEUS OF THE BED NUCLEI OF THE STRIA TERMINALIS IN THE RATS / 解剖学报

The oval nucleus of the bed nuclei of the stria terminalis of the rats was found in a previous investigation be studded with the corticotropin releasing factor (CRF) and neurotensin (NT)-immunoreactive(ir) neurons. The present work was to study their distribution and the possible coexistence of these two neuropeptides in the neuron of oval nucleus. The CRF- and NT- ir neurons were demonstrated to be densely and evenly distributed in the nucleus, among which were scattered a substantial number of cells cocontaining CRF and NT.