title: In vitro measurement of rate of fluid secretion in rat isolated seminiferous tubules: effects of metabolic inhibitors and ions.
abstract: 1. An in vitro technique for measuring secretory rate in rat isolated seminiferous tubules is described. 2. The basal rate of fluid secretion was 0-44+/-0-06 nl. cm-1 min-1 (S.E.) (n=21). The rate was found to be inhibited by cooling, addition of metabolic inhibitor 2,4-dinitrophenol (2-5 x 10(-4) M) and removal of glucose from the incubating solution. This indicates that fluid secretion in isolated rat seminiferous tubules is an energy dependent process. 3. Removal of K+ from the incubating medium inhibited the secretory rate in the isolated seminiferous tubules, whereas a fivefold increase in [K+]0 to 23-5 mM had no effect. The secretory rate was also unaffected by the absence of Cl- in the peritubular fluid. 4. Removal of Ca2+ from the peritubular medium caused a rise in the secretory rate. 5. Ouabain (10(-3) M) and acetazolamide (4 x 10(-5) M) caused a fall in the rate of fluid secretion in isolated seminiferous tubules. 6. These results are discussed in relation to the nature of the ionic secretion produced in the tubules.
mesh_terms: D000086:Acetazolamide / Q000494:pharmacology; D000818:Animals; D000963:Antimetabolites / Q000494:pharmacology*; D001693:Biological Transport, Active; D002118:Calcium / Q000494:pharmacology; D002712:Chlorides / Q000494:pharmacology; D004140:Dinitrophenols / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D010042:Ouabain / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D012636:Secretory Rate / Q000187:drug effects; D012671:Seminiferous Tubules / Q000187:drug effects / Q000378:metabolism*; D013696:Temperature; D013737:Testis / Q000378:metabolism*
chemical_list: D000963:Antimetabolites; D002712:Chlorides; D004140:Dinitrophenols; D010042:Ouabain; D005947:Glucose; D000086:Acetazolamide; D011188:Potassium; D002118:Calcium