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M.A. Masini et al.
ANP-Like Immunoreactivity in Cardiac Structures
In teleosts the heart has four chambers, the sinus venosus, atrium, ventricle
and a short, sometimes completely absent, conus arteriosus arranged in
sequence. The sinus venosus and atrium wiIl be considered together. Strong
rANP-like immunoreactivity was detected immunohistochemically in the
atrial myocytes of C. hamatus, Cryodraco antarcticus, Notothenia neglecta
and C. gunnari. Numerous cardiocytes, in the subepicardial region and in
the trabeculae, were intensely immunostained, especially in their
perinuclear zone (Fig. 4). The atrium of T. bernacchii gave weaker
immunoreactivity, the cardiocytes were less numerous, but the localization
was similar in the two species. The atrial cardiocytes showed stronger ANP
immunoreactivity than the ventricular cardiocytes. In the ventricle of C.
gunnari and N neglecta, a number of cardiocytes, localized in the
trabeculae, were immunolabeled (Figs. 5,6). There was no immunostaining
in the ventricles of Chionodraco and Trematomus.
Fig. 4. aANP immunoreactivity in atrial cardiocytes of N. neglecta. Immunoreactivity is
concentrated in the perinuclear region. Peroxidase - antiperoxidase (PAP). x 400
Figs. 5,6. a-rANP immunoreactivity in ventricular myocytes of C. gunnari (Fig. 5) and N.
neglecta (Fig. 6). PAP. x 350
M.A. Masini et al.
ANP-Like Immunoreactivity in Cardiac Structures
In teleosts the heart has four chambers, the sinus venosus, atrium, ventricle
and a short, sometimes completely absent, conus arteriosus arranged in
sequence. The sinus venosus and atrium wiIl be considered together. Strong
rANP-like immunoreactivity was detected immunohistochemically in the
atrial myocytes of C. hamatus, Cryodraco antarcticus, Notothenia neglecta
and C. gunnari. Numerous cardiocytes, in the subepicardial region and in
the trabeculae, were intensely immunostained, especially in their
perinuclear zone (Fig. 4). The atrium of T. bernacchii gave weaker
immunoreactivity, the cardiocytes were less numerous, but the localization
was similar in the two species. The atrial cardiocytes showed stronger ANP
immunoreactivity than the ventricular cardiocytes. In the ventricle of C.
gunnari and N neglecta, a number of cardiocytes, localized in the
trabeculae, were immunolabeled (Figs. 5,6). There was no immunostaining
in the ventricles of Chionodraco and Trematomus.
Fig. 4. aANP immunoreactivity in atrial cardiocytes of N. neglecta. Immunoreactivity is
concentrated in the perinuclear region. Peroxidase - antiperoxidase (PAP). x 400
Figs. 5,6. a-rANP immunoreactivity in ventricular myocytes of C. gunnari (Fig. 5) and N.
neglecta (Fig. 6). PAP. x 350