ACTA ENDOCRINOLOGICA (BUC)

Context. Betel nut is consumed by millions of people for stress reduction and increased capacity to work. One of its components is arecoline which is useful for Alzheimer and schizophrenia; it also influences endocrine and gonadal functions. Objective. Objective is to examine whether arecoline can influence pineal-testicular function in metabolic stress. Design. Rats were deprived of food or water or treated them with arecoline, each separately for 5 days. Subjects. Pineal and testis with sex accessories were studied. Methods. Ultrastructural (pineal, testis, Leydig cells and prostate), hormonal (melatonin and testosterone) and other parameters (fructose and sialic acid) were examined. Pineal indoleamines were quantitated by fluorometric method; testosterone by ELISA, and carbohydrate fractions by spectrophotometric methods. Results. Inanition/ water deprivation caused pineal stimulation ultrastructurally (with enlarged synaptic ribbons) and elevation of melatonin level, but reproductive dysfunction by ultrastructural degeneration of Leydig cells and prostate with fall of testosterone, fructose and sialic acid concentrations. Arecoline treatment showed reversed changes to those of metabolic stress, but arecoline treatment in metabolic stress showed same results as in metabolic stress. Conclusion. The findings suggest that arecoline cannot alter the action of metabolic stress on pineal-testicular activity in rats.

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Context. The grey mullet, Mugil cephalus, is an edible fish of high economic importance. Breeding biology with reference to hormonal/growth factor regulation of oocyte maturation needs to be known for its commercial production. Objective. The present study was conducted to examine the potency of maturation inducing hormones, chorionic gonadotropin (hCG), bovine-insulin, and insulin like growth factor1 (h-IGF-1) I on ovarian steroidogenesis and oocyte maturation. Design. The role of hormones and growth factors on steroidogenesis and oocyte maturation was investigated using specific inhibitors, Wortmannin for phosphatidylinositol-3 (PI3) kinase, trilostane for 3β-hydroxysteroid dehydrogenase, 1-octanol and 1-heptanol for gap junctions, actinomycin D for transcription and cycloheximide for translation of signal molecules. Methods. Actions of hormonal and growth factors were examined for steroidogenesis, by radioimmunoassay and oocyte maturation by germinal vesicle breakdown (GVBD). Specific inhibitors were used to determine the cell signaling pathways, PI3 kinase. Results. All the inhibitors attenuated the hCGinduced oocyte maturation (GVBD%), steroidogenesis including transcription, translation, gap junctions and PI3 kinase signaling. These inhibitors failed to inhibit h-IGF-I and b-insulin-induced oocyte maturation, steroidogenesis, translation and PI3 kinase signaling. Conclusion. hCG induces oocyte maturation via steroid dependent pathway involving gap junctions, transcription, translation and PI3 kinase signaling, unlike h-IGF-I and b-insulin in the mullet.