Flow cytometric evaluation on the age-dependent changes of testicular DNA contents in rats

An age-dependent cellular change of DNA contents in the testis of Sprague-Dawley rats was investigated by flow-cytometric method. Testicular cell suspensions at the age of 4, 5, 6, 7, 8, 10, 12, 16 and 26 weeks were prepared and stained with propidium iodide. The relative proportions in the number of mature and immature haploid (1n), diploid (2n), S-phase and tetraploid (4n) cells were calculated. The proportion in the number of mature haploid cells was sharply increased to the age of 10 weeks (about 38%), thereafter increased slightly to the level of 42% at the age of 26 weeks. The proportion of immature haploid cells was dramatically increased to the age of 6 weeks, then maintained at the level of 20 to 30% thereafter. The proportion of diploid cells was 64% at the age of 4 weeks, then decreased gradually through the age of 26 weeks. The proportion of S-phase cells was increased to the age of 4 weeks, then maintained at a plateau level to the age of 26 weeks. The proportion of tetraploid cells were about 26% at the age of 4 weeks, then decreased gradually to the age of 26 weeks. These results suggest that the proportions of testicular cells may depend on the age of the rat and that the flow cytometric method may be useful in the evaluation of the spermatogenic status with regard to accuracy and sensitivity.

Effect of ethylene glycol monoethyl ether on the spermatogenesis in pubertal and adult rats

The effects of ethylene glycol monoethyl ether (EGEE) on testicular cell populations in pubertal (5 weeks old) and adult (9 weeks old) male rats were investigated by a flow cytometric method. A total of 50 rats (in number, 25 pubertal and 25 adult rats) was divided into 5 experimental groups including 0 (control), 50, 100, 200, and 400 mg EGEE/kg of body weight. The animals were administered by gavage for 4 weeks. In adult rats, the treatment of EGEE at the dose of 400 mg/kg of body weight decreased significantly the populations of haploid, while it increased those of diploid and tetraploid cells. In pubertal rats, the treatment of EGEE at the dose of 400 mg/kg of body weight caused only minimal changes in the relative percent of testicular cell types. These results suggest that the effects of EGEE on testicular function in pubertal rats appear to be less pronounced than in adult rats.

Influence of Cortex mori on the Capsaicin-induced Neurogenic Inflammation / 대한해부학회지

The root bark of mulberry (Morus alba L. Cortex Mori and other plant of the genus Morus) has been used as an antiphlogistic, diuretic, and expectorant in herbal medicine, and the crude drug is known as "Sangbaikpi" in Korea. Capsaicin, a neurotoxin extracted from a red peppers, has selective effects on peptide-containing C-fiber and induces the release of neuropeptides from sensory nerve ending. But, any reports about the influences of Cortex mori (CM) on the capsaicin-induced neurogenic inflammation were not found, and the precise mechanism of capsaicin-induced neurogenic inflammation remains incompletely understood. The purpose of this study was to determine whether CM could inhibit the capsaicin-induced cutaneous reaction, and to find out its action mechanism. For this purpose, influences of CM on the capsaicin-induced cutaneous reaction (vascular permeability) in back skin of Sprague-Dawley rat, capsaicin-induced histamine release, calcium influx and the change of intracellular cAMP level in rat peritoneal mast cell were estimated. Results obtained were as follows; 1. Pretreatment of CM inhibited remarkably the capsaicin-induced cutaneous reaction. 2. The capsaicin-induced histamine release was inhibited by pretreatment with CM. 3. Capsaicin-induced calcium influx into mast cell was also inhibited by pretreatment with CM. 4. Capsaicin-induced decrease of cAMP level in the mast cell was inhibited significantly by pretreatment with CM. These results suggest that CM contains some substances with an anti-neurogenic inflammatory activity which inhibit the capsaicin-induced cutaneous reaction through the mechanism of mast cell stabilization.