Micron, 1976, Vol. 7: 297-298. Pergamon Press. Printed in Great Britain.

Abnormal sperm from rhesus monkeys

JOHN MATHEWS and T. J. LOBL Research Laboratories, The Upjohn Company, Kalamazoo, MI 49001, U.S.A.

A morphologic defect in sperm obtained from each of two Jersey bulls was reported by Blom (1966), and Blom and Birch-Andersen (1966). This 'Dag ' defect was shown by light microscopy as a strong coiling or folding of spermatozoan tails. By electron microscopy, individual sperms were seen as a group of cross-sections at various levels of the tail with the group of cross-sections enclosed by a single membrane. Variations from the typical 9-}-2 arrangement of tail fibres were seen in some cross-sections.

We wish to report strikingly similar findings in sperm obtained by electro-ejaculation from Rhesus monkeys after oral dosage with 1-(2,4- diehlorobenzyl) indazol - 3 - carboxylic acid. Treated monkeys (5 daily oral doses, 50mg/kg) show rapid decline in sperm count and motility until after 4 weeks they are essentially a z o -

spermic. After an eclipse phase lasting four weeks or longer, sperm counts slowly increase but most of these sperm show strong tail coiling and, therefore, very low motility. SEM examina- tion shows that indeed the tails are tightly coiled and the coil is apparently enclosed by a membrane. T E M examination of these recovery sperm shows an identical picture to that seen by Blom and Birch-Andersen in the 'Dag ' defect sperm, i.e. multiple cross-sections enclosed by a loose membrane with some cross sections showing abnormalities in the 9 + 2 arrange- ment.

A defect of apparent genetic origin in bull sperm has been almost exactly duplicated by oral administration of a drug to Rhesus monkeys. Recent findings suggest that many of the features of this defect can be produced in monkey sperm

Fig. 1. Coiled tail sperm showing profiles in planes parallel to and transverse to the plane of coiling, x 10,500. Bar = l~m.

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2!)8 .I. Mathcws and T. J. Lobl

Fig. 2. Scanning electron micrograph of coiled tail sperm. Note the membram~ enclosing the tail. ~ 4000. Bar : l~xm.

in vitro by p lac ing no rma l sperm in a hypo ton ic env i ronment . A s imilar system was s tudied by Drevius (1975) who noted the effect of hypo ton- ic i ty on bull spermatozoa .

REFEP.ENCES

Blom, E., 1966. Nature, Lond., 209: 739.

Blom, E. and Birch-Andersen, A., 1967. In: Proc. 5th World Congress on Fertility and Sterility, Stockholm, 1966. Westin, B. and Wiqvist, N. (eds.), p. 602. Excerpta Mediea Foundation, New York.

Drevius, L. O., 1975. In: Proc. 2nd Internal. Symp. on the Functional Anatomy of the Spermatozoan, Wenner- Gren Center, 1973, Afzelius, B. A. (ed.), p. 373. Pergamon Press, Oxford.