title: Humoral pathway for transfer of the boar pheromone, androstenol, from the nasal mucosa to the brain and hypophysis of gilts.
abstract: Signaling and priming pheromones play an important role in intraspecies behavioral and sexual interactions and in the control of reproduction. It is generally accepted that pheromones act by stimulating the dendritic receptors in the mucus-imbedded cilia of olfactory neurons massed in the olfactory epithelium. The boar pheromone androstenol, known to induce sexual behavior in pigs, is 1 of 2 pheromones that have been chemically defined, tritiated and thus made available for use in studies. In Experiment 1, sexually mature cyclic gilts at Days 16 to 21 of the estrous cycle were humanely killed and the heads separated from the bodies. The heads were attached to a perfusion system using heated, oxygenated, heparinized, autologous blood. A total amount of 10(8) dpm (758 ng) of 3H-5 alpha-androstenol (3HA) was either infused into the angularis oculi veins that drain the nasal cavities (n = 7) over a 5-min period or applied through intranasal catheters onto the mucose surface (n = 16) for 2 min. In both groups frequent blood samples were collected from the carotid rete and from venous effluent. Concentration of 3HA in the arterial blood of the carotid rete after direct (into angularis oculi veins) or indirect (onto the nasal mucosa) administration of 3HA into veins draining the nasal cavities was significantly higher than background radioactivity before 3HA administration (P < 0.0001 and P < 0.05, respectively). The 3HA was selectively accumulated (compared with the respective control tissue) in the neurohypophysis (P < 0.001), adenohypophysis (P < 0.01), ventromedial hypothalamus (P < 0.05), corpus mammillare (P < 0.01), and perihypophyseal vascular complex (P < 0.001). In a second in vitro experiment, active uptake of 3HA into the nasal mucosa of the proximal, respiratory segment of the nasal cavity was observed. These results demonstrate a humoral pathway for the transfer of pheromones from the nasal cavity to the hypophysis and brain. Androstenol was taken up by the respiratory part of the nasal mucosa, resorbed into blood, transported to the cavernous sinus and transferred into the arterial blood of the carotid rete (supplying the hypophysis and brain), and then selectively accumulated in the hypophysis and certain brain structures.
authors.affiliation: Division of Reproductive Endocrinology and Pathophysiology, Institute of Animal Reproduction and Food Research of The Polish Academy of Sciences, Olsztyn, Poland.
authors.forename: T
authors.initials: T
authors.lastname: Krzymowski
authors.forename: W
authors.initials: W
authors.lastname: Grzegorzewski
authors.forename: S
authors.initials: S
authors.lastname: Stefańczyk-Krzymowska
authors.forename: J
authors.initials: J
authors.lastname: Skipor
authors.forename: B
authors.initials: B
authors.lastname: Wasowska
mesh_terms: D000737:Androstenols / Q000493:pharmacokinetics*; D000818:Animals; D001921:Brain / Q000502:physiology*; D004971:Estrus; D005260:Female; D008297:Male; D009297:Nasal Mucosa / Q000502:physiology*; D010675:Pheromones / Q000493:pharmacokinetics* / Q000502:physiology; D010902:Pituitary Gland / Q000502:physiology*; D012726:Sexual Behavior, Animal; D013552:Swine; D013739:Testosterone / Q000493:pharmacokinetics; D014018:Tissue Distribution; D014316:Tritium
chemical_list: D000737:Androstenols; D010675:Pheromones; D014316:Tritium; D013739:Testosterone