A survey of sperm, potassium and sodium concentrations in the tubular fluid of the hamster epididymis

Abstract

Tubular fluid samples obtained in vivo by micropuncture from 5 separate locations along the hamster epidiymal duct were analyzed with ultramicro methods for sperm, sodium, and potassium concentrations. Net secretion or absorption of fluid, sodium, and potassium was calculated from the data. There is a slight drop in sperm concentration from the caput to the corpus as a result of a 13 percent increase in fluid volume between these two sites (P<0.02). There is no significant alteration in sperm concentration nor is there any net fluid movement between the corpus and the cauda. The potassium concentration in the caput of 39.3 ± 4.8 mEq/1 is significantly higher than the concentrations in the proximal cauda, distal cauda and epididymal vas of 20.8 ± 1.1 mEq/1, 23.9 ± 1.0 mEq/l, and 22.2 ± 0.9 mEq/1, respectively. Forty-five percent of the potassium present in the caput is absorbed between the caput and the proximal cauda. The concentrations of sodium in the caput and corpus of 28.4 ± 0.6 mEq/1 and 31.1 ± 2.0 mEq/1, respectively are higher than the sodium concentrations of 13.6 ± 1.2 mEq/1, 6.1 ± 0.5 mEq/1, and 6.7 ± 06 mEq/1 in the three sampled caudal sites (P<0.01). Approximately 75 percent of the sodium present in the caput is absorbed between the caput and the distal cauda