Blood and Nerve Supply of the Male Genitalia
The testis derives its blood supply from the testicular artery, which branches directly from the abdominal aorta a short distance caudal to the renal artery of the same side. Within the spermatic cord, the testicular artery assumes a tortuous arrangement.
The artery is embedded in the likewise convoluted mass of the testicular vein, the pampiniform plexus. The artery of the ductus deferens from the internal pudendal artery supplies the ductus deferens and may also provide some arterial blood to the epididymis and testis.The external pudendal artery, a branch of the deep femoral artery, passes through the inguinal canal and supplies the scrotum and prepuce. In most domestic species, a branch of the internal iliac artery, the internal pudendal artery, supplies most of the penis, urinary bladder, urethra, and accessory sex glands. The blood supply to the penis of the horse is more extensive than in other species, with additional contributions by the obturator artery, which passes through the obturator foramen of the pelvis, and the external pudendal artery after it passes through the inguinal canal.
The autonomic innervation of the testis is composed of sympathetic nerves. These autonomic nerve fibers accompany the testicular artery. sympathetic input affects activity in the blood vessels and smooth muscle fibers. The dorsal nerve of the penis is a continuation of the pudendal nerve, which is derived from ventral branches of sacral nerves. It passes along the dorsum of the penis to ramify in the glans penis. sensory fibers from the glans provide the afferent limb of reflexes for erection and ejaculation.