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Evident differences in the ammoniacal silver staining pattern of histones were demonstrated for neurones of different layers of adult rat cerebellar cortex. These differences were formed during postnatal differentiation. It has been also shown for Purkinje and granular cells that time-course of age-dependent changes in histone staining are not coincident with that for template activity of these cells.  相似文献   

3.
Tonic activity of neurons of the superior cervical sympathetic ganglion was recorded by the "sucrose gap" method and in the 4th and 5th lumbar sympathetic ganglia with the aid of focal nonpolarizing electrodes in acute experiments on anesthetized cats and rabbits. The preganglionic fibers of the ganglia were left intact. Stimulation of the depressor nerve not only sharply inhibited the tonic activity of the ganglia but also led to the appearance of electropositive potentials of 0.7 ± 0.2 mV in the superior cervical ganglion and 20–250 µV in the lumbar ganglia. The amplitude of this potential was unchanged by atropine (1 · 10–6M). A similar effect occured without stimulation of the depressor nerve, after division of the preganglionic fibers or blocking of their conduction; it is attributed to the cessation of preganglionic tonic impulses which induce not only spikes, but also many EPSPs in neurons of the ganglion. Their frequency in the lumbar ganglia was 4/sec. Summation of these EPSPs leads to constant electronegativity of the ganglion surface relative to the postganglionic fibers, and its disappearance is recorded as a positive potential. Stimulation of the depressor nerve thus does not induce IPSPs in the ganglion; consequently, the inhibition of synaptic activity observed under these circumstances is located in the CNS and not in the ganglion.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 6, No. 5, pp. 519–524, September–October, 1974.  相似文献   

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A study of the tonic electrical activity of nerves containing preganglionic and postganglionic fibers in the superior cervical and stellate sympathetic ganglia of cats and rabbits has shown that this activity consists of groups of spikes synchronous with the pulse or respiration, and occurs on a background of irregular low-amplitude impulses. The frequency of spikes is higher (250/sec) in nerves containing preganglionic fibers than in those containing postganglionic fibers (100/sec). Groups of spikes in a nerve containing preganglionic fibers correspond in some preparations to groups of spikes of lower frequency in a nerve containing postganglionic fibers of the same ganglion; in other preparations, this correspondence was lacking, apparently due to the absence of synaptic contacts between those groups of pre- and postganglionic neurons whose activity was recorded. Neurons send axons to different nerves (cardiac and vertebral) of the stellate ganglion discharged synchronously in some preparations, and asynchronously in others. Where synchronization was observed, the neurons discharged in rhythm with cardiac contractions.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 1, No. 3, pp. 303–308, November–December, 1969.  相似文献   

6.
Summary Paravertebral (superior cervical and stellate), prevertebral (coeliac-superior mesenteric, inferior mesenteric) and pelvic (hypogastric) sympathetic ganglia of the rat were investigated by enzyme histochemistry to ascertain the distribution of nicotinamide adenine dinucleotide phosphate diaphorase (NADPH-diaphorase) activity. In the paravertebral ganglia the majority of the sympathetic neuronal perikarya contained lightly and homogeneously distributed formazan reaction product but there was a range of staining intensities amongst the neuron population. In contrast, in the prevertebral ganglia, intense NADPH-diaphorase staining was present in certain neurons. Firstly, a population of neurons of the coeliac-superior mesenteric ganglion complex were surrounded by densely NADPH-diaphorase-positive baskets of fibres and other stained fibres were seen in interstitial nerve bundles and in nerve trunks connected to the ganglion complex. Secondly, in both the inferior mesenteric ganglion and hypogastric ganglion there were many very intensely NADPH-diaphorase positive neurons. Stained dendritic and axonal processes emerged from these cell bodies. In both ganglia this population of neurons was smaller in size than the lightly stained ganglionic neurons and commonly had only one long (presumably axonal) process. The similarity of these highly NADPH-diaphorase-positive neurons with previously described postganglionic parasympathetic neurons in the hypogastric ganglion is discussed.  相似文献   

7.
Summary The presence of neurofilament (NF)-like and glial fibrillary acidic protein (GFAP)-like immunoreactivities was studied in sympathetic ganglia of adult rats and guinea pigs during normal conditions and after perturbation. In the superior cervical ganglion (SCG) of normal rats, many ganglion cells and nerve fibers show NF immunoreactivity. Some of these nerve fibers disappear after preganglionic decentralization of SCG; this indicates the presence of a mixture of preand postganglionic NF-positive nerves in the ganglion. Cuts in both preand postganglionic nerves result in a marked increase in GFAP immunoreactivity in SCG, whereas NF immunoreactivity increases in nerve cell bodies after preganglionic cuts. Only a few ganglion cells show NF immunoreactivity in the normal SCG of guinea pig. All intraganglionic NF-positive nerves are of preganglionic origin; decentralization abolishes NF immunoreactivity in these nerve fibers. The inferior mesenteric ganglion, the hypogastric nerves and colonic nerves in guinea pigs contain large numbers of strongly NF-immunoreactive nerve fibers.When the SCG of adult rat is grafted to the anterior eye chamber of adult rat recipients, both ganglionic cell bodies and nerve fibers, forming on the host iris from the grafted ganglion, are NF-positive. As only the perikarya of these neurons normally exhibit NF immunoreactivity, and the terminal iris arborizations are NF-negative, it appears that the grafting procedure causes NF immunoreactivity to become more widespread in growing SCG neurons.  相似文献   

8.
Differences have been found between age-related shifts of DNA template activity of sympathetic neuron chromatin of normal and guanethidine-desympathized rats. The mean level of DNA template activity in mature neurons was the higher the heavier the desympathization of rat. In the ganglia of guanethidine-treated rats a subpopulation of neurocytes was revealed with an unusually high nucleolar-to-nucleoplasmic label ratio, never observed in control rats. The maturational disturbances in the course of alterations in histones visualized by ammoniacal silver, as well as shifts in the percentage of specifically stained nuclei are proportional to the level of desympathization. These changes in histones can be interpreted as a preliminary acceleration and aging of guanethidine-treated rat ganglia which are proportional to the number of destructed cells.  相似文献   

9.
Abstract— Immunosympathectomy was produced in Sprague-Dawley rats by the subcutaneous injection of 300 units of nerve growth factor (NGF)-antiserum (1.56 mg of freeze-dried serum)/g/day for 6 days, the first dose being given 5–8 hr after birth. The immunosympathectomized rats and their control littermates were killed 2½ and 7 months after birth. Ganglionic acetylcholinesterase and pseudocholinesterase activities were measured by an adaption (Kungman , Kungman and Pouszczuk , 1968) of the colorimetric method of Ellman , Courtney , Andres and Featherstone (1961). Following immunosympathectomy the activities of these enzymes decreased significantly in superior cervical, stellate, thoracic chain, cardiac (abdominal), coeliac and superior mesenteric ganglia. The reduction of the acetylcholinesterase activity was greater than expected in a number of sympathetic ganglia, e.g. superior cervical, stellate, coeliac and cardiac ganglia, if one considered that only the postganglionic neurons were affected by immunosympathectomy. The activities of these enzymes were also reduced in the cervical sympathetic trunks from NGF-antiserum-treated rats. By means of decentralization and axotomy it was shown that 45 per cent of the total ganglionic acetylcholinesterase activity was associated with the preganglionic and 55 per cent with the postganglionic elements of the superior cervical ganglion from control rats. It was concluded that immunosympathectomy also affects the preganglionic sympathetic neurons. It is not known whether this is a primary effect of the NGF-antiserum or a secondary effect resulting from the absence of over 90 per cent of the postganglionic sympathetic cell bodies.  相似文献   

10.
Abstract— The increase in tyrosine hydroxylase activity in mouse superior cervical ganglion during postnatal development was prevented by administration of the protein synthesis inhibitor cycloheximide. Surgical section of the preganglionic nerves in 4-day-old mice prevented the normal increases in tyrosine hydroxylase and monoamine oxidase activity in the ganglion during development. Surgical decentralization also prevented the developmental increases in ganglion size and cell numbers. The preganglionic fibres thus appear to exert a general regulatory effect on the growth and biochemical maturation of postganglionic adrenergic neurons in sympathetic ganglia. Administration of nerve growth factor to young mice failed to eliminate the differences in ganglion size, cell numbers and tyrosine hydroxylase activity between normally innervated and decentralized ganglia. Nerve growth factor, however, caused an increase in all these parameters in both control and decentralized ganglia–the magnitude of these increases being greatest in the control ganglia. Administration of carbachol and physostigmine to neonatal mice did not influence the normal development of tyrosine hydroxylase activity in the superior cervical ganglion.  相似文献   

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Summary Two postganglionic branches of the superior cervical ganglion enter the area of the carotid bifurcation in the rabbit and the cat. The common and external carotid arteries receive a rich adrenergic nerve supply, which can be demonstrated by fluorophores of biogenic amines appearing after formaldehyde treatment. The internal carotid artery is only sparsely innervated; however, it shows a dense sympathetic supply at the site of pressor receptors. Following removal of the superior cervical ganglion, a total loss of fluorescent adrenergic nerves occurs and degeneration of nerve endings possessing dense core vesicles is conspicuous. These nerve terminals are situated mainly subendothelially in the carotid body sinusoids; they only rarely terminate on type I cells.  相似文献   

13.
Summary By employing biochemical assay and histochemical enzyme techniques the effect of preganglionic sympathectomy on the cholinesterase (ChE) activity in the superior cervical ganglia of rats and hamsters was investigated. Biochemical assays indicate that the ChE activity in the superior cervical ganglia of adult rats and hamsters is 57.19 and 28.63 respectively (expressed in u moles acetylcholine hydrolyzed per min per g of tissue); two weeks after preganglionic denervation, about 50% and 60% of ChE activity are lost respectively. Histochemical enzyme examination reveals that in the rat superior cervical ganglion, the majority of the neurons are adrenergic with weak to moderate acetylcholinesterase (AChE) reaction and the minority of the neurons are cholinergic with strong AChE activity, while only one type of adrenergic neurons exhibits a weak AChE activity in the hamster superior cervical ganglion. The AChE activity is localized in the perinuclear area, in the cisternae of the rough surfaced endoplasmic reticulum, in the Golgi complex and on the plasma membrane of the hamster's neurons; it is mainly localized in the cisternae of the rough surfaced endoplasmic reticulum of the rat's neurons. AChE reaction product is also detected on the axolemmal membranes of the preganglionic nerve fibers in the sympathetic ganglia of rats and hamsters.After preganglionic sympathectomy, the AChE activity in the adrenergic neurons and in the preganglionic unmyelinated nerve fibers is markedly reduced, whereas the cholinergic neurons and preganglionic myelinated nerve fibers remain unchanged. On the basis of these results two conclusions have been reached: (1) The fact that strong AChE activity localized in the cholinergic neurons and preganglionic myelinated fibers is not influenced by denervation, suggests that these structures are able to produce AChE. (2) The reduction of AChE activity in the rat and hamster superior cervical ganglia two weeks after preganglionic denervation, observed by histochemical examination, can be correlated with a concomitant measurable reduction determined by biochemical assays.Supported in part by a grant from the National Science Council, Republic of China. The author wishes to express his gratitude to the Department of Pharmacology, College of Medicine, National Taiwan University, for the use of its equipment for biochemical assays  相似文献   

14.
Summary The ammoniacal silver reaction was used for localization of histones in meristematic root tip cells of Allium cepa. Electron microscopic observations showed that yellow or brown colour of interphase and prophase nuclei and brown nucleolar colour produced in the reaction coincides with the appearance of silver grains, about 400 Å in diameter, in the interphase and prophase chromatin and nucleoli. This together with the complete absence of staining reaction and silver grains in the cytoplasm could mean quite a specific reaction with histones and might suggest also that in these cells the site of histone synthesis is in the nucleolus.  相似文献   

15.
In in situ acute experiments, we intracellularly recorded the background activity (BA) from neurons of the superior cervical ganglion, which were antidromically identified by stimulation of the postganglionic nerve in close proximity to the submandibular salivary gland of the rat. According to the pattern of BA, these neurons could be classified into two groups; the respective units probably differ from each other in the number of active converging synaptic inputs. We hypothesize that these neurons are involved in the control of different aspects of function of the gland.Neirofiziologiya/Neurophysiology, Vol. 37, No. 1, pp. 26–31, January–February, 2005.  相似文献   

16.
M Fujiwara  K Kurahashi 《Life sciences》1976,19(8):1175-1180
The superior cervical ganglion was reinnervated by vagal afferent fibers following heterologous cross anastomosis between the superior cervical preganglionic trunk and the vagal trunk at the level of the supranodose ganglion in cats. The contractions of the nictitating membrane and the postganglionic action potentials from the external carotid sinus nerve in response to electrical stimulation of the vagal artificial preganglionic trunk in these operated cats were inhibited by treatment with tetraethylammonium and atropine. The choline acetyltransferase activities were measured by the radiometric method. The activities in cross anastomosed superior cervical ganglion were lower than those of normal superior cervical ganglion, but higher than those of chronically decentralized superior cervical ganglion. The activities in cross anastomosed nodose ganglion were lower than those of normal nodose ganglion, but higher than those of chronically decentralized superior cervical ganglion. These results further support the view that the primary afferent vagus artificially synapsed in the superior cervical ganglion is cholinergic.  相似文献   

17.
Neuronal activity in the in situ middle cervical ganglion of dogs was investigated using extracellular recording techniques. The recorded action potentials were frequently active during specific phases of the cardiac cycle, particularly during systole, and this activity persisted following acute decentralization of the ganglion. The activity of these action potentials was modified when systemic arterial pressure was altered by isoproterenol, noradrenaline, adrenaline, or partial occlusion of the aorta, whether in the intact or acutely decentralized preparation. These neurons were active between systolic pressures of 70 and 180 mmHg (1 mmHg = 133.322 Pa). Action potentials were frequently modified by mechanical distortion of the superior vena cava, ventricular epicardium, or adventitia of the aorta, whether the preparation was acutely decentralized or not. Seventy percent of these action potentials were unaffected by stimulation (1 ms, 4 V, 0.5 Hz) of a cardiopulmonary nerve and 27% were suppressed by such stimulation. Five of the neurons were activated by such stimulation. It is presumed that the latter neurons had axons in a cardiopulmonary nerve and most likely were efferent sympathetic postganglionic neurons. Sixty-three percent of these spontaneously active phase-locked units were modified by stimulation of a ramus or an ansa. It is postulated that some of the neurons in the middle cervical ganglia can be modified by afferent axons arising from receptors in thoracic organs, in particular from the great vessels and heart, whether in an intact or acutely decentralized preparation. The majority of these neurons are presumed not to be afferent neurons or efferent postganglionic neurons, as they are not activated directly by electrical stimulation of axons in cardiopulmonary nerves. Rather they are presumed to be interneurons. These results lend support to the thesis that considerable integration of neuronal activity related to thoracic cardiovascular dynamics occurs within the middle cervical ganglia of dogs.  相似文献   

18.
Abstract: Four main molecular forms of acetylcholinesterase (AChE) characterized by their sedimentation coefficients (5S, 7.5S, 11.5S, and 20S), are found in chick ciliary ganglion. After transection of the preganglionic nerve (denervation), total AChE activity in the ganglion dropped by 35% in 2 days. By then, 11.5s and 20s forms had diminished by 60 and 75% respectively, where as 7.5s remained practically unchanged. Since presynaptic structures disappeared 2 days after denervation, we inferred that at most 35% of total ganglion AChE was presynaptic: 11.5s and 20s might be mainly presynaptic and 7.5S, postsynaptic. At later time intervals. total AChE continued to decline up to day 5, possibly as a result of orthograde transynaptic regulation of the enzyme activity. After transection of postganglionic nerves (axotomy), total ganglion activity showed little change; 11.5s and 20s decreased by 40 and 6076, respectively, in 5 days, but these drops were compensated for by an early increase in 7 5S, which started the day after axotomy. After simultaneous transection of both pre- and postganglionic nerves (double section), total ganglion AChE dropped rapidly by 35% in 1 day and remained at that level up to 21 days. The 11.5S diminished rapidly by 60% in 1 day. The early increase of the 7.5s form induced by axotomy alone did not occur. Since the effect resulting from double section was not the equivalent of the cumulative effects observed after denervation and axotomy, respectively, the level of AChE forms in the ganglion may be regulated by reciprocal interaction of pre- and postsynaptic elements. After denervation and double section but not after axotomy alone, the contralateral non-operated ganglion exhibited a fall in the 20s form. This suggests that a transynaptic effect is exerted on AChE by the contralateral preganglionic neuron. Taken together, these results indicate that the various AChE molecular forms in chick ciliary ganglion are preferentially but not exclusively distributed as follows: the pre- and postganglionic axons contain mainly the 11.5S form, whereas nerve endings and synaptic structures are enriched in 20S, and ganglion cell bodies, in 7.5s.  相似文献   

19.
The adult rat superior cervical ganglion (SSG) contains low levels of galanin- and vasoactive intestinal peptide-(VIP) like immunoreactivity, with very few immuno-stained principal neurons. Immunoreactivity for both neuropeptides increases in these neurons after explanation or postganglionic axotomy in vivo. Northern blot analysis had demonstrated concomitant increases in mRNAs encoding these peptides. To localize cells in axotomized ganglia which increase their expression of these mRNAs, we performed in situ hybridization studies. In control SCG, only a few principal neurons contained mRNA for either galanin or VIP. After 48 h in organ culture, galanin mRNA was expressed in the majority of principal neurons. At 48 h after in vivo axotomy of both postganglionic trunks of the SCG, the internal and external carotid nerves, the distribution and number of neurons expressing galanin mRNA increased similarly to that seen in culture. Lesioning either trunk alone produced increases in galanin mRNA localized to those regions of the ganglion containing neurons that project into the lesioned trunk. Transection of the predominantly preganglionic cervical sympathetic trunk increased galanin mRNA expression in a small population of neurons that nerve trunk. The distributions of these labeled neurons, together with previous neuroanatomical studies, suggests that they had been axotomised by the lesions. Similar studies examining VIP mRNA expression demonstrated that although considerably fewer VIP mRNA expressing neurons than galanin mRNA expressing neurons were present after axotomy, the distribution of neuropeptide mRNA-positive cells were similar in both cases. These observations suggest that increases in the peptide galanin and VIP after nerve transection result from changes in the levels of their mRNAs in those neurons that have been axotomized. 1994 John Wiley & Sons, Inc.  相似文献   

20.
The localization of PKC-beta was studied in rat sympathetic neurons using a polyclonal antibody specific for the beta 1- and beta 2-subspecies. The tissues studied included the superior cervical (SCG) and hypogastric (HGG) ganglia and the target tissues of the SCG and HGG neurons: the submandibular gland, iris, prostate and vas deferens. PKC-beta-LI was found in nerve fibers in both ganglia. A proportion of the fibers in the SCG disappeared after decentralization, suggesting that the fibers were of both pre- and postganglionic origin. The somata of the HGG and SCG neurons expressed varying amounts of PKC-beta-LI, the majority of SCG neurons being labelled only after colchicine treatment. In all target tissues there were PKC-beta-immunoreactive nerve fibers in bundles, but the most peripheral branches of the fibers were negatively labelled. The results show that PKC-beta-LI is widely present in sympathetic postganglionic neurons with mainly quantitative differences. The lack of PKC-beta in the most peripheral branches of nerve fibers might be a general feature of sympathetic postganglionic neurons, suggesting that the participation of PKC-beta in neurotransmitter release and in other functions in nerve terminals in sympathetic adrenergic neurons is unlikely.  相似文献   

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