Effect of polychlorinated biphenyl, Aroclor 1254 on rat epididymis.

BACKGROUND& OBJECTIVES: Polychlorinated biphenyls (PCB), the synthetic chlorinated organic compounds, are known to decrease thyroid function, sperm count and fertility, and increase the risk of testicular cancer may cause serious effect on male reproduction. The objective of the present study was to study the effect of PCB, Aroclor 1254 on rat epididymal structure and function. METHODS: Adult male albino rats were treated ip with Aroclor 1254, 200 microg/kg body weight for 15 and 30 days. Serum levels of testosterone, estradiol, total triiodothyronine (T3), thyroxine (T4) and thyroid stimulating hormone (TSH) were measured by radioimmunoassay. The epididymal weight, sperm count, and caudal epididymal sialic acid, glyceryl phosphoryl choline (GPC) were also investigated. Histological studies were done on caput and caudal epididymal regions. RESULTS: Serum testosterone showed no change, but estradiol levels increased in 30 days treated animals, T3 and T4 levels decreased and TSH levels increased in both 15 and 30 days treated animals. Body weight, epididymal weight, sialic acid, GPC and sperm count were decreased only in 30 days Aroclor treated group. INTERPRETATION & CONCLUSION: The results suggested that Aroclor 1254 treatment for 15 and 30 days induced hypothyroidism in rats, but epididymal functions were altered only at 30 days treatment. The adverse effect of Aroclor 1254 (PCB) on epididymis might be due to indirect action through hormonal regulation.

Caffeine causes glycerophosphorylcholine accumulation through ryanodine-inhibitable increase of cellular calcium and activation of phospholipase A2 in cultured MDCK cells

Glycerophosphrylocholine (GPC) is a renal medullary compatible organic osmolyte that is derived from choline via phosphatidylcholine, which is catalyzed in part by phospholipase A2 (PLA2) and its degradation by GPC: choline phosphodiesterase (GPC: choline PDE). We found that caffeine elevated intracellular free calcium ([Ca2+]i) and GPC level in cultured MDCK cells, canine kidney epithelial cells, and propose a possible biochemical mechanism. When MDCK cells were incubated for 3 h with 1 to 10 mM caffeine, cellular GPC was elevated in a dose-dependent manner, and this occurred independently of the extracellular osmolality. Caffeine stimulated the rate of [14C]choline incorporation into [14C]GPC and PLA2 activity. Whereas, GPC: choline PDE activity was accompanied by less of increase. These enzyme changes demonstrate the increased net synthesis of MDCK GPC. In order to identify what triggers the PLA2 activation, [Ca2+]i was measured by using a fluorescence dye, Fura-2. Caffeine (10 mM) resulted in a typical transient increase in MDCK [Ca2+]i concentration, and this increase was greatly inhibited by pretreatment of MDCK cells with 10 mM ryanodine for 5 min. Ryanodine (10 mM) also inhibited the caffeine-induced stimulation of PLA2 activity. These findings provide the first evidence that caffeine in MDCK cells causes a ryanodine-inhibitable increase of [Ca2+]i and PLA2 activity, resulting in cellular GPC accumulation.

Semen biochemistry of leprosy patients.

Studies have been made on the semen of three categories (borderline, borderline tuberculoid and lepromatous) of leprosy patients to evaluate the seminal biochemical constituents viz. fructose, glycerylphosphorylcholine and acid phosphatase besides the physical properties viz. volume, pH, liquefaction time, sperm density and sperm motility. In all categories of leprosy patients, seminal pH, liquefaction time and sperm density underwent significant decline. The decline in the seminal volume and sperm motility was significant only in borderline leprosy. It was observed that seminal glycerylphosphorylcholine (GPC) concentration and acid phosphatase activity declined in all categories of leprosy patients but GPC showed a significant decline only in borderline tuberculoid and acid phosphatase declined significantly only in borderline and lepromatous leprosy.