Abstract
Transport of the epididymal contents was studied in vitro by filming, for 1-2.5 h, the movements of tiny, stained oil droplets injected through a micropipette into two regions of the lumen of the caput epididymidis: the most proximal part, with the widest outer diameter (region I), and the neighbouring, narrowest portion (region II). The movements of the oil droplets were pendular. Displacement, caused by a contraction of the wall spreading in either direction, was followed by a shorter, usually passive reflux leading to a small net displacement, delta l. The distance of transport during 5 min periods varied between 0.09 and 16.79 mm (median 1.0 mm) in region I and 0.05 and 3.62 mm (median 0.42 mm) in region II. Transport divided into periods when little or no net transport took place (slow transport) and periods when the transport was effective (fast transport). Although the periods of fast transport were infrequent, their significance in transport towards the ductus deferens was high. During 5 min sampling periods of fast transport, the pendular movements were longer in both regions: delta l was longer in region I and the probability of delta l being in the direction of transport was higher than during slow transport in both regions. The mean probability of delta l being in the direction of the ductus deferens was 0.63 in region I and 0.57 in region II. Higher frequency of pendular movements, longer delta l values and higher probability of delta l being towards the ductus deferens in region I than II suggest that the transport speed is higher in region I than II. Transport consisting of short steps occurring with variable probabilities in both directions is a stochastic process.
Full text
PDF










Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Akwari O. E., Kelley K. A., Steinbach J. H., Code C. F. Electric pacing of intact and transected canine small intestine and its computer model. Am J Physiol. 1975 Nov;229(5):1188–1197. doi: 10.1152/ajplegacy.1975.229.5.1188. [DOI] [PubMed] [Google Scholar]
- Amann R. P., Johnson L., Thompson D. L., Jr, Pickett B. W. Daily spermatozoal production, epididymal spermatozoal reserves and transit time of spermatozoa through the epididymis of the rhesus monkey. Biol Reprod. 1976 Dec;15(5):586–592. doi: 10.1095/biolreprod15.5.586. [DOI] [PubMed] [Google Scholar]
- Brown B. H., Duthie H. L., Horn A. R., Smallwood R. H. A linked oscillator model of electrical activity of human small intestine. Am J Physiol. 1975 Aug;229(2):384–388. doi: 10.1152/ajplegacy.1975.229.2.384. [DOI] [PubMed] [Google Scholar]
- Hinton B. T., Setchell B. P. Fluid movement in the seminiferous tubules and the epididymal duct of the rat [proceedings]. J Physiol. 1978 Nov;284:16P–17P. [PubMed] [Google Scholar]
- Hodgson B. J., Talo A. Spike bursts in rabbit oviduct. II. Effects of estrogen and progesterone. Am J Physiol. 1978 Apr;234(4):E439–E443. doi: 10.1152/ajpendo.1978.234.4.E439. [DOI] [PubMed] [Google Scholar]
- Jaakkola U. M., Talo A. Relation of electrical activity to luminal transport in the cauda epididymidis of the rat in vitro. J Reprod Fertil. 1982 Jan;64(1):121–126. doi: 10.1530/jrf.0.0640121. [DOI] [PubMed] [Google Scholar]
- Johnson A. L., Howards S. S. Intratubular hydrostatic pressure in testis and epididymis before and after long-term vasectomy in the guinea pig. Biol Reprod. 1976 May;14(4):371–376. doi: 10.1095/biolreprod14.4.371. [DOI] [PubMed] [Google Scholar]
- Jones R., Pholpramool C., Setchell B. P., Brown C. R. Labelling of membrane glycoproteins on rat spermatozoa collected from different regions of the epididymis. Biochem J. 1981 Nov 15;200(2):457–460. doi: 10.1042/bj2000457. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Orgebin-Crist M. C. Sperm maturation in rabbit epididymis. Nature. 1967 Nov 25;216(5117):816–818. doi: 10.1038/216816a0. [DOI] [PubMed] [Google Scholar]
- Portnow J., Hodgson B. J., Talo A. Simulation of oviductal ovum transport. Can J Physiol Pharmacol. 1977 Aug;55(4):972–974. doi: 10.1139/y77-133. [DOI] [PubMed] [Google Scholar]
- Portnow J., Talo A., Hodgson B. J. A random walk model of ovum transport. Bull Math Biol. 1977;39(3):349–357. doi: 10.1007/BF02462914. [DOI] [PubMed] [Google Scholar]
- Purvis K., Hansson V. Androgens and androgen-binding protein in the rat epididymis. J Reprod Fertil. 1978 Jan;52(1):59–63. doi: 10.1530/jrf.0.0520059. [DOI] [PubMed] [Google Scholar]
- Sarna S. K., Daniel E. E., Kingma Y. J. Simulation of slow-wave electrical activity of small intestine. Am J Physiol. 1971 Jul;221(1):166–175. doi: 10.1152/ajplegacy.1971.221.1.166. [DOI] [PubMed] [Google Scholar]
- Talo A., Hodgson B. J. Spike bursts in rabbit oviduct. I. Effect of ovulation. Am J Physiol. 1978 Apr;234(4):E430–E438. doi: 10.1152/ajpendo.1978.234.4.E430. [DOI] [PubMed] [Google Scholar]
- Talo A., Jaakkola U. M., Markkula-Viitanen M. Spontaneous electrical activity of the rat epididymis in vitro. J Reprod Fertil. 1979 Nov;57(2):423–429. doi: 10.1530/jrf.0.0570423. [DOI] [PubMed] [Google Scholar]
- Turner T. T., Hartmann P. K., Howards S. S. In vivo sodium, potassium, and sperm concentrations in the rat epididymis. Fertil Steril. 1977 Feb;28(2):191–194. doi: 10.1016/s0015-0282(16)42382-4. [DOI] [PubMed] [Google Scholar]