The nerve distribution in the testis of the cat

Kh. Wrobel et A. Gurtler, The nerve distribution in the testis of the cat, ANN ANATOMY, 183(4), 2001, pp. 297-308
Citations number
Categorie Soggetti
Experimental Biology
Journal title
ISSN journal
0940-9602 → ACNP
Year of publication
297 - 308
SICI code
The autonomous innervation of the feline testis was investigated by immunoh istochemistry and a modified acetylcholinesterase technique. The nerves rea ch the testis mainly by two routes: (1) with testicular artery and pampinif orm plexus to the cranial extremity (funicular contribution), (2) from the epididymal tail to the caudal extremity (caudal contribution). Within the t unica albuginea the funicular contribution supplies the cranial two thirds, whereas the caudal third of the tunica receives its nerves via the ligamen tous connection between testis and epididymal tail. The nerve bundles accom panying the testicular artery give branches to the arterial wall and the pa mpiniform plexus. When reaching the cranial testicular pole the bundles sep arate; the majority of them pass into the centrally located mediastinum tes tis, another large portion enters the tunica albuginea, particularly on its epididymal side. The septula testis are innervated from both sides, that i s from the mediastinum and from the tunica albuginea. In the cat, contrary to other mammals, all septula are innervated. Furthermore, nerve fibers occ ur regularly within the testicular lobules. Generally, the testicular nerve s of the cat are unmyelinated and mainly vascular nerves, but fibers are al so found within the connective tissue compartments of the testis. The vast majority of all autonomous testicular nerves are postjunctional sympathetic fibers. Terminal ramifications of cholinergic fibers are exclusively obser ved in the wall of medium-sized arterioles within mediastinum, septula and lobuli testis. Neuropeptide Y is the most frequent peptidergic transmitter in feline testicular vascular plexuses. The amount of calcitonin gene-relat ed peptide-positive fibers is also remarkably high in the testis, but prefe rs a location within the stroma of the tunica albuginea, mediastinum and se ptula. In the cat, Leydig cells occur not only in intertubular locations, b ut also as intratunical and mediastinal Leydig cells. In all three localiza tions solitary nerve fibers are observed between Leydig cell groups. These fibers are generally dopamin-beta-hydroxylase- and tyrosine hydroxylase-pos itive, some contain calcitonin gene-related peptide and, very few, substanc e P.