Figure 1.
Macroscopic view of the hemipenis ofCrotalus durissus terrificus partially everted.
In A and B it is possible to observed the stretched m. retractor penis basalis (arrow) contouring the pedicle of the hemipenis, and participating in sulcus spermaticus fold (arrowhead). In C and D it is possible to observes the dissected muscle (arrow) and its loop shape.
Figure 2.
Macroscopic view of the hemipenis ofCrotalus durissus terrificus.
A: Everted hemipenis, B. inverted hemipenis. musculus retractor penis magnus (MRM), black arrow points to artery and white arrow points to veins.
Figure 3.
Scanning electron microscopy of the basal region of hemipenis ofCrotalus durissus terrificus.
A: Wide view of cross-section in basal region showing two corpora cavernosa, one internal (CCI) and another external (CCE), in central part appear the musculus retractor penis magnus (MRM). B: Magnified view of MRM and sulcus spermaticus (SS), layers of smooth muscle cells (SMC) and a part of CCE beside SS is observed. C: A view of central part of MRM., showing the central sinusoid (CS) in this muscle and limiting its space there is a tunica albuginea (TA), muscle cells (MC). D: View of MRM where the muscle cells bundles (MC) and the central sinusoid (CS) are observed. E, F and G: Details of sinusoids in external limit of CCE, it is possible to observe a great number of lacuna (LA) some of those full of erythrocytes (*).
Figure 4.
Scanning electron microscopy of the trunk region of hemipenis ofCrotalus durissus terrificus.
A: Wide view of the trunk showing two cavernous bodies, one internal (CCI) and another external (CCE), near the sulcus spermaticus (arrowhead); the musculus retractor penis magnus (MRM.), spines rounding the trunk (**) and is observed that the number of trabecula is greater in CCE than in CCE. B: Detail of external surface of hemipenis in an area without spines, the epithelial cells (EC) covering the tunica albuginea (TA) of external face of hemipenis are observed. C: Detail of layers of connective tissue under epithelial cells presented in B. The connective tissue presented is non-cornified and is composed of two-to-five layers. D and E: Detail of insertion point of spine (*) in CCE in the trunk region, arrows point to smooth muscle bundles that anchor the spine in hemipenis.
Figure 5.
Scanning electron microscopy of the apex region of hemipenis ofCrotalus durissus terrificus.
A: Wide view of the transversal cut from apex region of hemipenis, it is possible to see two cavernous bodies, one internal (CCI) and another external (CCE.), and the musculus retractor penis magnus (MRM), arrows point to external and internal sphincters. B: Detail of sulcus spermaticus (SS) and CCE, delimited by external (white arrow) and internal (black arrow) sphincters. The trabeculas (*) delimit the lacunar space. C: Detail of net formed by smooth muscle bundles (trabeculas), arrows point to cluster of erythrocytes rested in bundles. D: Detail of central sinusoid (CS), arrow points to transversal sinusoids inside the muscle. E: Detail of lacunar spaces (LA), with different sizes, presents in external sphincter and in epithelial surface.
Figure 6.
Light microscopy of hemipenis fromCrotalus durissus terrificus.
A: Transversal cut of musculus retractor penis magnus showing muscles cells (MC) and the central sinusoid (CS). B: Detail of central sinusoid in a transversal cut of musculus retractor penis magnus. The central sinusoid (CS) is layered by smooth muscle cells (MC) and a endothelium, erythrocytes (arrow) are observed inside the sinusoid. C: Detail of corpus cavernosum internal, smooth muscle cells (SM); surrounding lacunar spaces (LA). D: Detail of a trabecula, the connective tissue (CT) are surrounded by smooth muscle cells (*) and endothelial cells (arrow) forming lacunar spaces (LA).