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Motile rabbit sperm tails that lack heads are immobilized by antibody plus complement. Accordingly, immunological immobilization may not necessarily require the extensive sperm acrosomal damage previously reported in immobilized normal sperm.
Sperm tails and bronchial cilia from Polynesians with bronchiectasis were examined in the electron microscope. The outer doublet tubules of the axonemal skeleton in these organelles either lacked dynein arms or had only partial arms. Various other cilial abnormalities were common. The sperm were immotile and pulmonary mucociliary clearance was reduced or absent.
Selenium is necessary for normal sperm tail development in the rat. The biochemical locus of this requirement was investigated by intratesticular administration of (75Se)SeO3-2. Sperm were labeled primarily in tail keratin, a disulfide-stabilized fraction obtained by extracting isolated tails with sodium dodecyl sulfate (SDS). By incubation in 1% SDS-0.2 mM dithiothreitol, followed by sonication and centrifugation, the 75Se was separated from a residue rich in S and Zn, composed of dense fibers and connecting pieces. The extracted 75Se-labeled material was non-dialyzable, sensitive to pronase, retained most of its bound isotope following carboxymethylation, and displayed only one radioactive component, of 17,000 daltons, during SDS-polyacrylamide gel electrophoresis. It is suggested that the labeled moiety is a selenopolypeptide whose function is critical for normal assembly of the sperm tail.
The zinc content was determined in semen samples from four young Danish Jersey bulls showing the typical 'Dag defect' (greater than 50% strongly coiled or bent sperm tails). Two of the bulls were half brothers. Semen samples from 14 normal fertile Jersey bulls served as controls. The normal material showed a zinc content in the centrifuged sperm of 190 +/- 15.8 mug/g d.w. and in the seminal plasma 81 +/- 31.2 mug/g d.w. In the four abnormal bulls the following elevated values were found: in the centrifuged sperm 310 +/- 109.5 mug/g d.w. and in the seminal plasma 137 +/- 75.2 mug/g d.w. (see figs. 1 and 2). One of the Dag defect's main localizations, the outer dense tail fibers, has a very high zinc content and this fact together with the heredity of the defect make further studies most promising.
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Motile spermatozoa from the golden hamster have been arrested by rapid freezing and then fixed with glutaraldehyde at low temperature after substitution with ethylene glycol. As far as can be judged, the flagellar waveforms thus stabilized are similar to those seen in living sperm; in contrast, fixation in glutaraldehyde, without prior freezing, induces agonal changes in flagellar conformation. The characteristics waveform after freeze substitution contains three bends. Approx. half of these flagella are entirely planar. The rest are three dimensional, with the third bend displaced in a regular way from the plane containing the proximal two bends. From the geometry of these flagella, it is concluded that the plane of action of a given bending cycle undergoes a clockwise twist (from a forward viewpoint) as the cycle is succeeded by new bending cycles. This "twisted plane" undulation is quite different from helical movement. The twisting seems to occur abruptly, between cycles, as if each bending cycle has a preferred plane of action. The mechanism underlying the twisting is uncertain. However, on the basis of the angular displacements between the preferred planes, and the findings from electron microscopy, the following idea is presented as a working hypothesis: that, if the most proximal plane of bending is topographically determined by peripheral doublet 1, then successive distal planes of action are influenced predominantly by doublets 2, 3, etc., in clockwise sequence. The merits and weaknesses of this hypothesis are discussed.
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Large numbers of spermatozoa with bent or coiled tails were found in the ejaculates of rhesus monkeys treated with 1-(2,4-dichlorobenzyl-indazole-3-carboxylic acid (DICA) (50 or 500 mg/kg for various periods). The defect appeared only in spermatozoa in the cauda epididymidis and consisted of axoneme disarrangement and loss of the fibre doublets. The coil was completely enclosed in a membrane.
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A case of sterility in an 18-month-old bull of the Holstein-Friesian breed was investigated. A semen sample sent to the laboratory showed a very low sperm concentration and abnormal sperm morphology. On the preliminary examination, the major sperm defect (60-70%) seemed to be tailless heads. When higher manification was used it was found that most of the defective heads had a short tail rudiment, a tail stump 2-3 mu long. Loose sperm tails were seldom seen in the smears. The defect has been described previously from Canada where it has occurred in different breeds, including Holstein-Friesians. The dam of the Danish bull in question was inseminated with imported American semen, and the sire is one of the most demanded Holstein-Friesian bulls at present. The possible heredity of the defect is discussed.
We investigated six men and a woman suspected of suffering from congenital immotility of cilia. All had chronic airway infections, and the men had immotile spermatozoa. The woman and three men had Kartagener's syndrome. The investigations included measurements of the mucociliary transport in the lower airways and ultrastructural studies of the sperm tails or respiratory cilia (or both). Mucociliary transport was significantly delayed. Sperm tails lacked dynein arms in five patients. Respiratory cilia from the women and two men lacked dynein arms and were irregularly oriented. The results support the hypothesis that a congenital defect in the cilia and sperm tails will cause chronic respiratory-tract infections and male sterility--the immotile-cilia syndrome. In about half these patients there will also be a situs inversus--i.e., Kartagener's syndrome.
Mucociliary transport in the tracheobronchial tract was studies in 2 subjects by having them inhale a radioactively tagged test aerosol and by taking external measurements of the radioacitivity in the lungs for 2 hours. Both subjects had living, yet immotile seprmatozoa; the sperm tails lacked normal dynein arms, which are essential for the bending movements of sperm tails as well as of other cilia. The subjects were classified as suffering from Kartagener's syndrome (situs inversus, chronic sinusitis, and bronchiectasis) and were shown to have an extremely slow, probably absent transport. The results of the study were in agreement with a recent hypothesis explaining Kartagener's syndrome as due to a genetic lack of dynein arms. An estimate of the importance of mucociliary transport as a protective mechanism of the lung may be possible by examining patients suffering from Kartagener's syndrome.
Bull semen was collected artifically and vitamin A was determined in the intact spermatozoa, the acrosomes and the sperm tails. The results show that over 90% of the total vitamin A in the spermatozoa was present in the acrosomes and that the sperm tails were completely devoid of vitamin A. The concentration of vitamin A varied from 224 to 364 ng/10-9 spermatozoa.
Kartagener's syndrome (KS) is a hereditary disease with typical symptoms of situs inversus, bronchiectasis, and chronic infections of the nasal mucosa. Autosomal recessive inheritance cannot be doubted on account of repeated observations of affected sibs and parental cansanguinity. The bronchopulmonary symptoms in sibs, however, cannot be explained by this mode of inheritance. Recent clinical findings and electron microscope investigations suggest that KS is a special form of manifestation within the immotile cilia syndrome. This disease combines the typical bronchial and nasal symptoms of KS with sterility in the male due to immotile sperm tails and, as a facultative symptom, situs inversus. Thus, sibs with bronchiectasis but without situs inversus are also classified under this syndrome. The symptoms mentioned are caused by an abnormal morphology of bronchial cilia and sperm tails, which can be demonstrated by electron microscopy. The dynein arms normally attached to the nine microtubular doublets and providing a normal ciliary movement are lacking. It is assumed that during early embryonic life ciliary beats in the growing embryo determine the type of laterality. When ciliary movements are absent laterality may develop fortuitously, thus effecting a situs inversus in about half the affected cases. The numerical evaluation of pedigrees from the literature supports this assumption.