effect of infection of the filarial parasite brugia malayi - Pondicherry ...

433 DISCUSSION
Testosterone is a sensitive indicator of the reproductive function (Rikihisa et al.,
1984). The present study demonstrates that the testosterone production in the host was
decreased in the infected animals. Reduction in testosterone level may be due to degadation
or decreased testosterone output from the testes due to parasitic infection (Rikihisa et al.,
1985). Decreased number of leydig cells or their topological changes in distribution with
reference to blood and lymphatic vessels might cause decreased out put of testosterone in
testes. Rikihisa el al. (1985) reported a decrease in rat testosterone due to Taenia
taeniafonnis infection. A similar kind of inhibition is reported in Toxoplasma gondii
infection (Dias and Stahl, 1984).
y-GTP in the testes is primarily found in the sertolt cells of mammals and had been
used as a sertoli cell marker in rats (Hodgen and Sherins, 1973; Lu and Steinberger, 1977;
Fukuota et a/., 1990)). Hodgen and Sherins (1973) found an abrupt increase in y-GTP
activity in prepubertal rat testis which coincided with the cessation of sertoli cell division and
their maturation. Krueger er al. (1974) measured 1-GTP activity in testis of vitamin-A
deficient rats. The level of this enzyme ~ncreased during germinal cell depletion. The
observed increase in y-GTP In B.malayi infected animals suggests that the sertoli cell has
been damaged and germinal cells depleted. These adverse effects due to B. malayi infection
have been confirmed by the hstopathological studies (sec 4.4.2.1.3).
Among vertebrate species, somat~c cells often contain lactic dehydrogenase (LDH)
in an array of five isoenzymes. The unique LDH-X isoenzyme occurs in the mature testis of
mammals (Blackshaw, 1973; Linda and Mayeda, 1974; Taylor and Gutteridge, 1986). It is a
unique marker of the germinal cell rnaturatlon and the production of the sperms (Lalwani et
al., 19%). Hodgen (1983) show4 the coincidence of LDH-X with the histological
appearance of pachytene spematocytes. ltoh and Ozasa (1985) and Aganval el al. (1997)
reported impcurment of testicular function due to cadmium chloride administration to rats,
i.e., a marked duction in testicular LDH-X. The occurrence of LDH-X either in traces or