The aim of this study is to describe the presence of neuroendocrine (NE) cells (paraneurons), producing biogenic amines and/or peptidergic hormones, in the female urethra of cattle, sheep, pigs, and horses, by means of histochemical and double labeling immunofluorescent techniques. 5-Hydroxy-tryptamine-, chromogranin A-, cholecystokinin- and somatostatin-containing NE cells are present in the urethral epithelium of all the species studied, with the unique exception of the lack of somatostatin cells in the horse. Paraneurons containing 5-hydroxytryptamine colocalized with chromogranin A or cholecystokinin were also found in all subjects. Such active substances are hypothesized to play a role in the contraction of the urethral musculature, emission of urogenital fluids, and inhibition of endocrine and exocrine secretions.

Appearance of vascular changes in SHRSPs, before any MRI-detectable brain lesion, is coupled to active neural proliferation in the SVZ. With disease progression, only newborn astrocytes can survive, likely because of the neurotoxicity triggered by brain oedema and oxidative stress.

Summary. The first appearance and distribution of VIP-containing nerve structures were studied in the gut of embryonal, newly hatched and adult domestic ducks.Immunoreactive structures appeared in the mesenchyme of the gizzard-duodenum junction (antrum) at 5 days of incubation, and soon after diffused both cranially and caudally. Early in development, VIP-positive cell bodies were more numerous than positive fibres, appearing 3 days before the latter. Later on, the positive cell bodies decreased in number while the fibres increased. In the foregut, VIP-positive structures firstly appeared in the myenteric plexus while in the mid-and hindgut they appeared simultaneously in the myenteric and submucous plexuses. The gastrointestinal VIP-innervation in newly hatched ducks differed from that of the adult because of the incomplete development of its mucosal component.The findings obtained indicated following: The time interval from 13 to 17 days of incubation seems critical for the growth of the gastrointestinal VIP-containing neurons. The molecular factors regulating the appearance of neuronal phenotypes are probably synthesized early in the avian gizzard development. VIP is widely diffused in the rectum where it may play important roles in regulating the onset and synchronism of peristaltic and anti-peristaltic movements.

Endocrine cells scattered in organic mucosae were defined "Neuroendocrine" (NE) cells because they constitute a section of the Diffuse Neuroendocrine System (DNES). Such cells have never been evidentiated in the normal endometrium. By means of histochemical and immunohistochemical techniques, NE cells, some of which contain the hormone somatostatin, are described in the glandular epithelium of the uterine horn in non-pregnant, non-castrated, young and adult sows. As is known, the uterine horn is the organ of pregnancy in the pig. The localization, distribution and morphology of the uterine NE and somatostatin-containing cells are reported and the importance of their function, in the pregnant and non-pregnant porcine uterus, is discussed.

The presence of CCK-containing neuroendocrine cells in human adenomatous prostates, and the colocalization of CCK together with serotonin in the same cell, have been demonstrated by means of an immunohistochemical technique and by a double labeling immunofluorescent staining. CCK-containing neuroendocrine cells had a focal distribution in the prostates and sometimes showed dendrite-like cytoplasmic processes. The major part of CCK (96.55%) colocalized with serotonin. CCK probably stimulates muscle contraction and endocrine/exocrine secretions in the urogenital tract.