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1.
Arylazido aminopropionyl adenosine triphosphate (ANAPP3), a photoaffinity label, antagonized specifically adenine nucleotide-induced contractions of the guinea pig vas deferens. Irradiation of tissues with visible light in the presence of ANAPP3 resulted in an irreversible antagonism, which was prevented when adenosine triphosphate was present. In the absence of light, the antagonism was reversible and may have resulted from an autoinhibition phenomenon. Responses to acetylcholine, histamine, norepinephrine, and potassium chloride were not affected by ANAPP3.  相似文献   

2.
日本沼虾的雄性生殖系统由精巢、输精管、端壶腹和雄性生殖孔组成。精巢外被一层结统组织膜,内为许多生植小管,小管壁包括生精上皮和管壁上皮,生精上皮不断向管腔内增殖,形成不同发育阶段的雄性生殖细胞,输精管分为前输精管(细段)、中输精管(螺旋段)和后输精管(直段),其管壁均由高柱状上皮和矮柱状上皮构成,具有分泌功能;端壶胞壁肌肉层厚,其它结构与输精管壁相仿。精巢的发育季节性明显。  相似文献   

3.
日本沼虾的雄性生殖系统由精巢、输精管、端壶腹和雄性生殖孔组成。精巢外被一层结统组织膜,内为许多生植小管,小管壁包括生精上皮和管壁上皮,生精上皮不断向管腔内增殖,形成不同发育阶段的雄性生殖细胞,输精管分为前输精管(细段)、中输精管(螺旋段)和后输精管(直段),其管壁均由高柱状上皮和矮柱状上皮构成,具有分泌功能;端壶胞壁肌肉层厚,其它结构与输精管壁相仿。精巢的发育季节性明显。  相似文献   

4.
詹光杰  奚耕思 《安徽农业科学》2009,37(12):5518-5520
首次对拟黑多刺蚁内生殖进行系统解剖观察。结果发现,拟黑多刺蚁的雌性生殖系统由卵巢、输卵管、中输卵管、受精囊、生殖腔和雌性附腺等结构组成,为典型的多滋式卵巢;雄性生殖系统由精巢、侧输精管、输精管、贮精囊、射精管、雄性附腺及阴茎等结构组成,雄性附腺发达,贮精囊不明显,婚飞前雄蚁的精巢及精巢小管已逐渐退化,精巢小管的数量与其他种类蚂蚁存在一定差别。  相似文献   

5.
Both natural (-)-morphine and its unnatural enantiomer (+)-morphine exert an excitatory action on electrically stimulated contractions of rat vas deferens. Preexposure to (-)-morphine results in cross-tolerance to the inhibitory action of beta-endorphin. (-)-Naloxone and its stereoisomer (+)-naloxone also exert an excitatory action, but only (-)-naloxone bocks the inhibtory action of beta-endorphin. Thus morphine exerts a dual action on a peripheral organ: one an inhibitory action mediated by the stereospecific endorphin receptor that is blocked stereospecifically by naloxone, the other an excitatory action mediated by a nonstereospecific receptor that is not blocked by naloxone. The opiate abstinence syndrome is seen as due to the unmasking of the excitatory action of opiates when its concomitant inhibitory influence is removed by selective blockade by naloxone or weakened by selective tolerance. The view that the rat vas deferens is devoid of morphine receptors is now seen as arising from a reverse example of morphine's dual action: the masking of the inhibitory action of morphine by its concomitant and more potent excitatory action.  相似文献   

6.
Serum dopamine- -hydroxylase: decrease after chemical sympathectomy   总被引:5,自引:0,他引:5  
Dopamine-beta- hydroxylase is an enzyme that is localized to catecholamine-containing vesicles in sympathetic nerves and the adrenal medulla, and is also found in the serum. Treatment of rats with 6-hydroxydopamine, a drug which destroys sympathetic nerve terminals, leads to a decrease in serum dopamine-beta-hydroxylase activity. The decrease is not due to an effect on the adrenal medulla or to an increase in circulating inhibitor or inhibitors of enzyme. These data represent evidence that at least a portion of the circulating dopamine-beta-hydroxylase activity arises from sympathetic nerve terminals.  相似文献   

7.
输水影响下胡杨胸径生长量时空变化   总被引:2,自引:0,他引:2  
以塔里木河下游14次人工输水对荒漠河岸林修复过程的生态效益评估为长期目标,利用近10 a在塔里木河下游阿拉干断面的大量野外调查数据,探讨了胡杨胸径在不同时间和空间尺度上对人工输水的响应。结果显示,随着输水次数和输水量的稳步增加,河道两边地下水位逐渐抬升,胡杨胸径生长量明显增大;但是,由于不同年间输水次数、输水季节和输水量有差异,各年间胡杨胸径生长量呈现出不同的增加趋势,胸径生长量与河道输水量大小相互对应,累计输水量与胸径生长量成正比,两者之间的指数函数模型拟合度为0.928。随着离河道距离的增加,地下水位抬升不明显,胡杨胸径生长量也逐渐变小,胸径生长量与离河道距离之间的回归模型拟合度为0.965,离河道距离与胸径生长量成反比。离河道距离与不同胸径级胡杨胸径生长量之间的回归模型拟合度(以胸径级增大的趋势)分别为0.876,0.879,0.849和0.837;与胸径级增大的趋势耦合。由此得出,胸径级大的胡杨胸径生长量随离河道距离的变化差异没有比胸径级小的胡杨大,说明胡杨胸径级越大(即胡杨进入老龄阶段),其胸径生长量与地下水埋深之间的关系则不明显。  相似文献   

8.
[目的]探究绵羊附睾视黄酸结合蛋白——载脂蛋白5(lipocalin5,LCN5)在睾丸、附睾不同区段及输精管组织表达特点及其精子中的定位,为LCN5在雄性生殖器官中的功能研究提供理论依据.[方法]选择体重相近((65.23±1.95)kg)、体况良好、健康无病的9月龄公绵羊6只,其中3只使用假阴道法采集精液,3只做无...  相似文献   

9.
Serum dopamine-beta-hydroxylase activity: sibling-sibling correlation   总被引:7,自引:0,他引:7  
Dopamine-beta-hydroxylase activity is released into the blood with catecholamines from the adrenal medulla and sympathetic nerves. This enzyme activity has been measured in the blood of 317 normal children and 227 normal adults. A significant sibling-sibling correlation of serum dopamine-beta-hydroxylase values was found in the 94 sibling pairs tested. Frequency distributions of serum enzyme values in both children and adults suggest the existence of two populations with regard to serum activity of this enzyme.  相似文献   

10.
Norepinephrine methylation in fetal rat adrenals   总被引:8,自引:0,他引:8  
The activity of phenylethanolamine-N-methyl transferase, the enzyme that methylates norepinephrine to form epinephrine, increases rapidly in the fetal rat adrenal during the day preceding epinephrine accumulation. The developmental increase in enzyme activity and the accumulation of epinephrine are prevented by fetal hypophysectomy (decapitation). Administration of adrenocorticotrophic hormone or cortisol acetate largely reverses the effect of fetal decapitation.  相似文献   

11.
The rate of disappearance of intracisternally administered [(3)H]norepinephrine from rat brain gradually declines as a multiphasic exponential function of time. Conversion to [(3)H]normetanephrine accounts for a larger fraction of the [(3)H]norepinephrine released in the brain shortly after its intracisternal injection than that released at later times. Pools of norepinephrine in the brain thus appear to differ in their turnover rates and pathways of metabolism. The pool of norepinephrine with a rapid rate of turnover and an appreciable conversion to normetanephrine, identified by the techniques reported here, may correspond to a pool of newly synthesized norepinephrine in the brain.  相似文献   

12.
The number of vesicles released at excitatory synapses and the number of release sites per synaptic connection are key determinants of information processing in the cortex, yet they remain uncertain. Here we show that the number of functional release sites and the number of anatomically identified synaptic contacts are equal at connections between spiny stellate and pyramidal cells in rat barrel cortex. Moreover, our results indicate that the amount of transmitter released per synaptic contact is independent of release probability and the intrinsic release probability is high. These properties suggest that connections between layer 4 and layer 2/3 are tuned for reliable transmission of spatially distributed, timing-based signals.  相似文献   

13.
The lateral geniculate nucleus is organized in such a way that, initially at least, information from the one eye is almost exclusively segregated from that from the other eye. Single-unit recording, however, confirms the histological evidence that bilateral integration does take place. A small number of cells (< 8.5 percent) receive afferents directly from both optic nerves and are discharged by stimulating either nerve (direct interaction). More common is delayed interaction, where the cells are discharged independently by either optic nerve but only after a relatively long latency. Indirect interaction effects also occur.  相似文献   

14.
汤军芝  刘玉东  刘苗  采克俊 《安徽农业科学》2010,38(6):2886-2887,2907
[目的]初步研究黄粉虫(Tenebrio molitor)的雄性生殖系统。[方法]以石蜡切片和HE染色观察分析黄粉虫成虫的睾丸与豆状附腺组织。[结果]黄粉虫雄性生殖系统由1对精巢、1对管状附腺、1对豆状附腺、1对输精管和1根射精管组成。黄粉虫的精子发生是一个动态的过程,精巢由数目巨大的精巢小管聚集盘曲组成,精巢小管中孕含着处于各个发育时期的生精细胞。[结论]为进一步研究黄粉虫生殖腺发育情况奠定基础。  相似文献   

15.
3H]adenosine triphosphate: release during stimulation of enteric nerves   总被引:8,自引:0,他引:8  
The isolated taenia coli of the guinea pig takes up tritiated adenosine, adenosine monophosphate, adenosine diphosphate, and adenosine triphosphate, in preference to tritiated inosine and adenine. After uptake, [(3)H]adenosine is converted and retained primarily as [(3)H]adenosine triphosphate. Tritium is released from taenia coli treated with [(3)H]adenosine upon activation of the nonadrenergic inhibitory nerves. These results are consistent with the previous evidence that adenosine triphosphate may be the transmitter from the nerves.  相似文献   

16.
中华乌塘鳢鱼精巢的形态结构观察   总被引:5,自引:0,他引:5  
主要研究了中华乌塘鳢鱼精巢的形态结构.中华乌塘鳢鱼精巢分为两部分,前段为生精部,线形;后段为贮精囊,末端1cm区域有薄膜状结构.中华乌塘鳢鱼精巢生精部为小叶型结构,贮精囊为网状管腔结构.  相似文献   

17.
The rate of disappearance of intracisternally administered tritiated norepinephrine from rat brain is decreased after a single dose of the tricyclic antidepressant imipramine. During long-term administration of imipramine, however, the rate of disappearance of tritiated norepinephrine from brain gradually increases, and there is a concurrent decrease in the content of endogenous norepinephrine in brain. These findings may help to explain why antidepressant effects are observed clinically only after long-termn treatment with imipramine.  相似文献   

18.
The defining morphological feature of chemical synapses is the vesicle cluster in the presynaptic nerve terminal. It has generally been assumed that vesicles closest to release sites are recruited first during nerve activity. We tested this by selectively labeling the "readily releasable" pool, those vesicles released first during physiological stimulation. The readily releasable vesicles were not clustered close to the presynaptic membrane but instead were dispersed almost randomly throughout the vesicle cluster. Thus, vesicles are not recruited according to proximity to release sites but are mobilized differently, perhaps by being peeled from the surface of the cluster.  相似文献   

19.
Release of catecholamines and specific protein from adrenal glands   总被引:5,自引:0,他引:5  
Rabbit antiserums directed against a purified protein obtained from the catecholamine storage vesicles of the adrenal medulla of the cow were used to study the mechanism of secretion from the adrenal medulla. During secretion evoked by acetylcholine in isolated perfused adrenal glands, catecholamines and the specific intravesicular protein were released in relative amounts comparable to those present in the intact gland. Thus catecholamines are apparently released from the storage vesicles by a process resembling reverse pinocytosis.  相似文献   

20.
Brain norepinephrine: enhanced turnover after rubidium treatment   总被引:4,自引:0,他引:4  
After biosynthesis of norepinephrine was inhibited, treatment of rats for 10 days with rubidium chloride (0.6 milliequivalent per kilogram of body weight) caused an increase in the rate of disappearance of norepinephrine in the brainstem but not in the telencephalon. Also the utilization of intracisternally injected tritiated norepinephrine was increased and was accompanied by a shift in the pattern of norepinephrine metabolism to normetanephrine. These data suggest that greater amounts of neuronally stored norepinephrine were released to central adrenergic receptors.  相似文献   

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