title: Increase in fluid viscosity during epididymal transit and the immobilization of rat epididymal spermatozoa.
abstract: A microcapillary method was developed to measure the viscosity of small volumes of undiluted epididymal fluid. Fluid from the cauda epididymis registered 82 +/- 17 centipoise which was much more viscous than fluid from the caput region (8 +/- 2 centipoise). Initiation of sperm motility was strongly suppressed in the viscosity range of 7 to 150 centipoise. A significant increase in the viscosity of fluid from the caput region was observed when immobilin in the fluid binds with a lectin from Jack fruit (Artocarpus heterophyllus). Thus, it is postulated that aggregation of the immobilin induced by a lectin-like material produced by the cauda epididymis may be a mechanism by which fluid viscosity is increased during epididymal transit.
mesh_terms: D000818:Animals; D001826:Body Fluids / Q000502:physiology*; D002197:Capillary Action; D004822:Epididymis / Q000502:physiology*; D006023:Glycoproteins / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins; D037102:Lectins / Q000378:metabolism; D008297:Male; D037121:Plant Lectins; D051381:Rats; D011919:Rats, Inbred Strains; D013081:Sperm Motility; D014783:Viscosity
chemical_list: D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; D037102:Lectins; D037121:Plant Lectins; C039654:immobilin protein, rat; C043696:jacalin