Effects of sympathetic denervation or chronic reserpine on potassium (42K) and chloride (36Cl) efflux from guinea-pig vas deferens.
Potassium (42K) or chloride (36Cl) efflux curves were determined in guinea-pig vas deferens from control, reserpine-treated animals (1 mg/kg/day i.p. for 5 days), and from animals whose vas deferens had been sympathetically denervated 1 week before. Steady-state 42K turnover in control tissues was 0.0052 +/- 0.0002 min-1; neither reserpine treatment nor sympathetic denervation changed this parameter signicantly. Control 36Cl turnover was 0.058 +/- 0.002 min-1 and it was unaffected by either procedure. Methoxamine (3 x 10(-6) to 10(-4) M) induced dose-related increases in the fractional exchange of 42K and 36Cl. These were of greater magnitude after sympathetic denervation or reserpine treatment. Furtrethonium also produced dose-dependent increases in 42K efflux; its dose-response curve was shifted 2.6-fold to the left of the control curve by reserpine treatment. These results indicate that interruption of adrenergic transmission to the guinea-pig vas deferens is associated with increased changes in membrane permeability to Cl and possibly K in response to drug activation of alpha-adrenergic and cholinegic receptors. It is suggested that the supersensitivity phenomenon observed in the guinea-pig vas deferens after reserpine or sympathetic denervation is, in part, related to improved transduction of drug-receptor interaction into ionic permeability changes.
D000818:Animals; D001834:Body Water / Q000378:metabolism; D002712:Chlorides / Q000378:metabolism*; D002713:Chlorine; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D011188:Potassium / Q000378:metabolism*; D011197:Potassium Radioisotopes; D011868:Radioisotopes; D012110:Reserpine / Q000494:pharmacology*; D013562:Sympathectomy; D014649:Vas Deferens / Q000187:drug effects / Q000378:metabolism*
D002712:Chlorides; D011197:Potassium Radioisotopes; D011868:Radioisotopes; D002713:Chlorine; D012110:Reserpine; D011188:Potassium