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Effect of Photoperiod in the Regulation of the Annual Testicular Cycle of a Subtropical Mammal,the Indian Palm Squirrel, Funambulus pennanti

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Biomedical and Environmental Sciences 1995年第1期8卷 65-73页

作者： A.B.SINGH CHANDRAMOHINICHATURVEDI departmentofzoology BanarasHinduUniversityVaranasi221005India departmentofzoology BanarasHinduUnive

In seasonally breeding subtropical mammal, the Indian pelm squirrel (Funambulus pennanti), reproductive recrudescence is initiated before the winter solstice followed by sexually active condition which extends until the end of summer season. Onset of seasonal regression coincides with the annual decrease in daily photoperiod and the increased level of relative humidity resulting from the arrival of monsoon at this latitude. To test the photoperiodic responses, the groupe of squirrels were exposed to natural day length (NDL), long day length (LD15:9), and Short day length (LD 6: 18) over a period of one year beginning from March. Squirrels of all these groupe were exposed to similar ambient temperature and humidity ***, the rate of testicular development was similar in control and long day squirrels attaining peak values in May (0.67 cm3) and June (0.7 cm3) respectively. Thereafter, while the gonads of controls regressed, the latter maintained a plateau. On the other hand, the gonads of short day squirrels regressed sharply until June (0.21 cm3)followed by spontaneous recrudescence and finally a plateau (0.55 cm3). These results indicate that initially squirrels are photosensitive (as long days are gonadostimulatory and short days are inhibitory) in the first half of summer season but eventually become refractory to the inhibitory effect of short days. Obvinusly, an acyclic condition is developed under constant long as well short day conditions maintaining the neurocndocrine-gonadal-axis in a continuously active state. We suggest that in nature although gonadal growth of this species does not synchronize with the increase in daily photoperiod, it is partially regulated by an interplay of annual photocycle and humidity conditions. Present study also indicates that this species has developed a strong photoperiodic mechanism which may surposs the reproductive effect of other environmental factors when maintained in constant conditions of day length.

关键词： In cycle Funambulus pennanti Effect of Photoperiod in the Regulation of the Annual Testicular Cycle of a Subtropical Mammal,the Indian Palm Squirrel

Functional Maturation of Neuroendocrine GonadalAxis is Altered by Specific Phase Relations of Circadian Neurotransmitter Activity in Japanese Quail

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Biomedical and Environmental Sciences 1995年第4期8卷 367-377页

作者： DORISPHILLIPS CHANDRAMOHINICHATURVEDI departmentofzoology BanarasHinduUniversityVaranasi－221005India departmentofzoology BanarasHinduUniv

The present study was designed to ascertain the effects of temporal relationship of circadian neural oscillations on puberty attainment and reproductive growth of Japanese Quail, Coturnix coturnix japonica. Serotonin and dopamine precursors (5-hydroxytryptophan, 5-HTP and L-dihydroxyphenylalanine, L-DOPA; 5 mg/ 100 g body weight) were injected daily, 8 and 12 h apart in two groups of one-day old chicks, while controls received two daily injections of normal saline. Weekly/ biweekly observations (body weight, cloacal gland size, testicular volume and activity, ovarian follicular diameter and rate of egg production) were made until 9 weeks of age, wben the experiment was terminated. Results indicate that 8 h relationship completely suppressed gonadal growth even under long photoperiod (LD 16:8), while a 12 h relationship induced precocious sexual maturity and increased the rate of reproduction (spermatogenesis and egg production). It is concluded that circadian phase relationship of serotonergic and dopaminergic activity may not only determine the onset of reproduction in this poultry species, but may also alter the rate of reproduction possibly by affecting photoperiodic mechanism of reproductive regulation

关键词： Activity

Lipid Peroxidative Damage by Arsenic Intoxication is Countered by Glutathione-glutathione-S-transferase System and Metallothionein in the Liver of Climbing Perch, Anabas testudineus

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Biomedical and Environmental Sciences 1998年第2期11卷 187-195页

作者： DEBAPRASADDAS DEBAPRIYASARKAR EnvironmentalToxicologyLaboratory DepartmentofZoologyVisuaBharatiUniversitySantiniketan731235 Envir

Arsenic (As) intoxication was examined in freshwater climbing perch (Anadas testudineus) following in vivo treatment for 2d at 1/10 LD50 and for 30d at 1/20 LC50. These exposures elicited no mortality, nor any apparent physiological distress. Lipid peroxidation (LPO), in terms of the production of malondialdehyde (MDA) and conjugated diene (CD),as the intoxication response, was prominent only after 48h at an arsenic dose of 1/10 *** was accompanied by a significant decline in the level of reduced glutathione (GSH) in the fish, with no change in the glutathione-S-transferase (GST) activity. In the 30-d exposure,the increase in LPO activity at day 15 was not significant but there was significant increase in GSH accompanied by a significant stimulation of GST activity. Interestingly, the induction of metallothionein (MT) by As was already evident during the short term exposure, and the response further stabilized during the chronic exposure. The results clearly indicate that the elevated MT and GSH status seen during chronic treatment may provide adequate protection against peroxidative damage by As.

关键词：砒霜中毒谷胱甘肽硫转移酶肝脏金属硫固脂质过氧化动物实验

Chloroform extract of Carica papaya seeds induces long—term reversible azoospermia in langur monkey

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Asian Journal of Andrology 2002年第1期4卷 17-26页

作者： LohiNK ManiB ReproductivePhysiologySection DepartmentofZoologyUniversityofRajasthanJaipus－302004India

AIM: To evaluate the antifertility activity of the chloroform extract of Carica papaya seeds by oral administration in langur monkey, Presbytis entellus entellus. METHODS: The chloroform extract of Carica papaya seeds, 50 mg/kg/day, was administered orally for 360 days to adult male langur monkeys. The sperm characteristics by light and electron microscopy, the sperm functional tests, the semen biochemistry, the serum testosterone level, the Leydig cell function, and the histology and ultrastructure of testis were determined to evaluate the antifertility activity and the blood biochemistry and hematology, to evaluate the toxicology. RESULTS: The extract gradually decreased the sperm concentration since days 30-60 of treatment with a total inhibition of sperm motility, a decrease in sperm viability and increase in sperm abnormality. Azoospermia was observed after day 90 of treatment and continued during the whole treatment period. Treatment withdrawal resulted in a gradual recovery in these parameters and 150 days later they reverted to nearly the pretreatment values. Morphological observation of the ejaculated sperm by light and scanning electron microscopy showed deleterious changes, particularly on the mid-piece. Sperm functional tests, viz., sperm mitochondrial activity index, acrosome intactness test and hypo-osmotic swelling test scored in the infertile range during treatment and returned to the fertile values 150 days after drug withdrawal. Histology of the testis revealed shrunken tubules, germ cell atrophy and normal Leydig cells. Ultrastructure of the testis showed vacuolization in the cytoplasm of Sertoli cells and germ cells. Loss of cytoplasmic organelles were evident in the spermatocytes and spermatids. Round spermatids showed loss of Golgi bodies, peripheral mitochondria and vacuolated cytoplasm, indicating maturational arrest. Leydig cell functional test indicated a mild inhibition of steroidogenic function. Haematology and serum biochemistry study di

关键词： Carica Animals Cercopithecidae Chloroform Contraceptive Agents Male Ejaculation Male Microscopy Electron Oligospermia Plant Extracts Research Support Non-U.S. Gov't Semen Sertoli Cells Solvents Sperm Count Spermatozoa Testosterone

Effect of papaya seed extract on contractile response of cauda epididyman tubules

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Asian Journal of Andrology 2002年第1期4卷 77-78页

作者： VermRJ ChinNJ departmentofzoology UniversitySchoolofSciencesGujaratUniversityAhmedabad380009India

AIM:To evaluate the administration of Carica papaya seed extract on the contractility of cauda epididymal tubules in male rats.METHODS:Adult male albino rats were administered intramuscularly papaya seed extract at a dose of 0.5 mg/kg/day for 7 days. Animals were killed, cauda epididymal tubules of 5 cm length were isolated and the contractile response to different concentrations of adrenalin (1-500 microg/25mL) was examined. In another group of animals, the contractile response was assayed 3 months after withdrawal of the treatment.RESULTS:Papaya seed extract brought about a significant decrease in the contractile response of epididymal tubules as compared with the control. After three months of papaya withdrawal, a nearly normal pattern of contraction was regained.CONCLUSION:Papaya seed treatment reversibly reduces the contractile response of cauda epididymal tubules.

关键词： Carica papaya Contractility Epididymis Epinephrine

Effect of Sarcostemma acidum stem extract on spermatogenesis in male albino rats

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Asian Journal of Andrology 2002年第1期4卷 43-47页

作者： VermPK SharA ReproductivePhysiologySection DepartmentofZoologyUniversityofRajasthanJaipur－302004India

AIM: To evaluate the possible antifertility activity of Sarcostemma acidum (Roxb) Voigt. stem extract in male rats. METHOD: Male rats were given 70% methanol extract of S. acidum stem orally at dose levels of 50 and 100 mg/kg/day for 60 days. Fertility was evaluated with mating test. Sperm motility and sperm density in cauda epididymides were also assessed. Biochemical and histological analyses were performed on blood samples and on the reproductive organs. RESULTS: S. acidum stem extract resulted in an arrest of spermatogenesis without any systemic side effect. Sperm motility as well as sperm density was reduced significantly. Treatment caused a 80% reduction in fertility at the 50 mg dose and complete suppression of fertility at the 100 mg dose. There was no significant change in RBC and WBC count, hemoglobin, haematocrit, sugar and urea in the whole blood and cholesterol, protein and phospholipid in the serum. The protein and glycogen content of the testes, fructose in the seminal vesicle and protein in epididymides were significantly decreased. Cholesterol in the testes was elevated. Treatment at both of the doses caused a marked reduction in the number of primary spermatocytes (preleptotene and pachytene), secondary spermatocytes and spermatids. The number of mature Leydig cells was decreased, and degenerating Leydig cells was increased proportionately. CONCLUSION: S. acidum stem extract arrests spermatogenesis in male rats without noticable side effects.

关键词： Plants Medicinal Animals Blood Cell Count Body Weight Cholesterol Contraceptive Agents Male Glycogen Leydig Cells Male Phospholipids Plant Extracts Rats Rats Sprague-Dawley Spermatids Spermatocytes Spermatogenesis

Biomonitoring of Anticholinesterase Pesticides in the Soil:Usefulness of Soil Collembola

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Biomedical and Environmental Sciences 1995年第3期8卷 232-239页

作者： PARTHAPRATIMCHAKRAVORTY SHAMBHUNATHBOSE 等 SoilZoologyLaboratory EnvironmentalToxicologyLaboratory DepartmentofZoologyVisvaBharatiUniversitySa

The impact of Methyl parathion and Carbaryl was evaluated on an ecologically important soil Collembola, Cyphoderus sp. Enzyme characteristics demonstrate substrate optimum at 1 10-2 mol/L temperature optimum at 30℃ with a pH requirement of 8.0. In vivo inhibition of whole body AChE reveals higher degree of inhibition by LD50 dose of Methyl parathion as compared to that of Carbaryl where maximum inhibition was noticed at the agricultural dose

关键词： In Biomonitoring of Anticholinesterase Pesticides in the Soil

Effects of Cimetidine, H_2 Receptor Antagonist,on Follicular and Luteal Developmentin the Mice

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Biomedical and Environmental Sciences 1994年第2期7卷 154-168页

作者： K.JAISWAL A.KRISHNA departmentofzoology BanarasHinduUniversityVaranasi221005India DepartmentofPhysiology UniversityofK

The effects of various doses, duration and frequency of cimetidine treatment on vaginal cycle, ovulation, ovarian histology and follicular kinetics were investigated. In addition,studies were performed to assess the reversibility in ovarian functions following withdrawal of cimetidine treatment.A statistically significant (P<0.05) decline in ovarian and uterine weights, but not in body and adrenal weights, were observed in females treated with cimetidine four times daily for long-term as compared with the controls. Ovarian and uterine weights recovered to pretreatment levels following withdrawal of the treatment. Cimetidine treatment caused irregularities in the reproductive cyclicity of *** treatment causes adverse effect on ovarian function depending on the time,duration and frequency of treatment. Treatment for only one day at proestrus induced significant (P <0.05) decline in ovulatory efficiency. However, administration of cimetidine, four times daily, for either 6 or 14 days caused ovarian dysfunction. The treatment depressed the number of healthy preantral and antral follicles as well as number of healthy corpus luteum (CL) in the ovary. Absence of healthy CL, presence of several atretic late antral follicles and reproductive acyclicity provide evidence for the failure of ovulation in mice treated with cimetidine four times per day for 14 days. Moreover, when cimetidine was administered twice daily, the ovaries also showed newly formed CL. The results, thus,suggest that the effects of cimetidine on ovulation are dependent on dose, duration and frequency of treatment. Blockage of ovulation in long-term cimetidine treated mice could be due to its influence on follicular atresia. Ovulation had occurred in these females after withdrawal of cimetidine treatment

关键词： Effects of Cimetidine H2 Receptor Antagonist,on Follicular and Luteal Developmentin the Mice

The Intertidal Pulmonate, Onchidium Tumidium,Uses Different Strategies to Survive Short Term and Long Term Anoxia

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中山大学学报论丛 1995年第3期15卷 208-210页

作者： C.B.Lim W.P.Low S.F.Chew Y.K.Ip departmentofzoology NationalUniversityofSingaporeDepartmentofZoologyNationalUniversityofSingaporeDepartmentofZoologyNationalUniversityofSingaporeDepartmentofZoologyNationalUniversityofSingapore

Onchidiumtumidiumisaslug-l******,itemergesfromitsburrow,***,itburrowsanddis

关键词： lactate succinate