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1.
We used a discontinuous Percoll density gradient centrifugation to prepare enriched populations of prolactin (PRL), growth hormone (GH), and folliculo-stellate (FS) cells from rat anterior pituitaries in order to characterize these various cell populations. After cell dissociation and centrifugation, enriched PRL cells (55% of total cells as determined by immunocytochemistry [ICC] were present in Fraction 1 (Fr1) (density ([d]) = 1.059). Fr2 (d=1.071) had enriched S100-positive FS cells (31% of total cells), but enriched GH cell (60% of total cells) were present in Fr3 (d=1.094). Interleukin 6 (IL-6) was secreted mainly by enriched PRL cells in Fr1 (350 pg/mL/106 cells) and Fr2 (194 pg/mL/106 cells), and much less by the enriched GH cells inFr3 (16 pg/mL/106). Proliferation studies with combined 3H-thymidine and ICC for pituitary hormones showed that only the PRL cell had significant prolifereative activity. Immunostaining showed that immediately after separation, all three isoforms of nitric oxide synthase (NOS) were expressed anterior pituitary cells. After 3 d of culture, there was a marked increase in nuclear staining for neuronal NOS (nNOS) in all three fractions, whereas inducible NOS (iNOS) and endothelial NOS (eNOS) rexpression did not change significantly. These results indicate that: 1. Enriched populations of PRL, FS, and GH pituitary cells can be readily obtained with a rapid discontinuous percoll density separation procedure. 2. PRL cells from different fractions of the gradient show differenet proliferation rates and IL-6 secretion varied in different enriched cell populations. 3. Although all three isoforms of NOS were expressed in rat pituitary cells, nNOS is the prindipal isoform in anterior pituitary cells, and its expression was icreased after 3 d of culture of anterior pitutuitary cells. 相似文献
2.
H. Asanuma A. Arnold P. Zarzecki 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1976,26(5):443-461
The effective spread of stimulating current for pyramidal tract (PT) cells and fibers was studied using a method of cancelling the shock artifacts and the following results were obtained:
相似文献
1. | The excitability of PT axon collaterals was as high as that of PT cells. |
2. | These axon collaterals extended as far as 1.0 mm horizontally from the PT cells. |
3. | The low threshold area for activation of a given PT cell was as wide as 3–4 mm2 on the surface of the cortex. |
4. | Intracortical microstimulation (ICMS) delivered to the PT cell layer produced direct (D) and indirect (I) descending volleys in the pyramidal tract, but ICMS to the superficial layer (III) produced only I-waves. |
5. | These I-waves grew significantly larger after 15–20 msec from the start of the train of stimuli. |
6. | It is concluded that either surface stimulation, or short train of ICMS is inadequate for delineating fine localization of motor function within the cortex. Longer train (30–40 msec) with high frequency pulses (300–400 cy/sec) can produce muscle contraction with much smaller currents, increasing the accuracy of measuring the localization of motor function. |
3.
Takehiro Tsukada Tom Kouki Ken Fujiwara Dini Ramadhani Kotaro Horiguchi Motoshi Kikuchi Takashi Yashiro 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2013,46(4):121-127
The anterior pituitary gland comprises 5 types of hormone-producing cells and non-endocrine cells, such as folliculostellate (FS) cells. The cells form a lobular structure surrounded by extracellular matrix (ECM) but are not randomly distributed in each lobule; hormone-producing cells have affinities for specific cell types (topographic affinity), and FS cells form a homotypic meshwork. To determine whether this cell and ECM organization can be reproduced in vitro, we developed a 3-dimensional (3D) model that utilizes hanging drop cell culture. We found that the topographic affinities of hormone-producing cells were indeed maintained (ie, GH to ACTH cells, GH to TSH cells, PRL to LH/FSH cells). Fine structures in hormone-producing cells retained their normal appearance. In addition, FS cells displayed well-developed cytoplasmic protrusions, which interconnected with adjacent FS cells to form a 3D meshwork. In addition, reassembly of gap junctions and pseudofollicles among FS cells was observed in cell aggregates. Major ECM components—collagens and laminin—were deposited and distributed around the cells. In sum, the dissociated anterior pituitary cells largely maintained their in vivo anterior pituitary architectures. This culture system appears to be a powerful experimental tool for detailed analysis of anterior pituitary cell organization. 相似文献
4.
O. G. Krivosheev N. A. Nabatchikova G. I. Pozdnyakova E. A. Syutkin V. A. Vinogradov V. Ya. Chernykh S. P. Veselova T. R. Saks F. E. Meertsuk 《Neuroscience and behavioral physiology》1989,19(4):341-345
1. | Surfagon, an analog of luliberin, possesses high biological activity, surpassing the biological activity of luliberin by a factor of 10 in the test of stimulation of secretion of gonadotropins by the rat pituitary in vivo and in the test of induction of ovulation in rats. |
2. | Surfagon has a prolonged effect on the secretion of gonadotropins in vivo and in vitro. |
3. | The use of various doses of surfagon permits selective stimulation of secretion only of LH or of LH and FSH by the pituitary in rats. |
5.
É. P. Bekhtereva 《Neuroscience and behavioral physiology》1976,7(3):211-214
1. | Administration of L-dopa in a dose of 20 mg/kg for 12 days leads to the premature onset of puberty in sexually immature female rats. |
2. | Administration of L-dopa in a dose of 100 mg/kg daily for 12 days inhibits the onset of puberty in sexually immature female rats. |
3. | Administration of L-dopa in a dose of 20 mg/kg daily for 3–4 weeks inhibits ovulation and causes an increase in the LH content in the pituitary of young sexually mature female rats. |
4. | L-dopa, when injected into rats with an irregular anovulatory cycle in a dose of 20 mg/kg (daily for 2 weeks) causes ovulation, alters the ratio between the phases of estrus and diestrus, and also changes the FSH and LH levels in the pituitary in 50% of cases. |
5. | Injection of L-dopa in a dose of 20 mg/kg into rats with spontaneous estrus restores their normal sex cycle and ovulation. |
6.
D. R. E. Jones 《Comparative Haematology International》1993,3(4):201-213
In autoimmune haemolytic anaemia (AHA) antibody(ies) are directed at ‘self’ red blood cells (RBC) and can effect their destruction.
This removal of RBC may be enhanced by the additional presence of complement on the cell membrane. The diagnosis of AHA requires
the demonstration of such antibody(ies), which are able to sensitise autologous erythrocytes in vivo. AHA has been described
in a variety of animal species but the techniques employed in the laboratory diagnosis have, generally, been extrapolated
from those used in human serology. The application of newer and more sensitive techniques to the assessment of RBC sensitisation
with antibody and complement, has improved the diagnosis of AHA. Furthermore, it is now possible to assess the significance
of the degree of RBC sensitisation and to evaluate treatment regimens.
Approaches to the assessment of RBC sensitisation are:
相似文献
1. | Agglutination tests |
a) | Broad spectrum antiglobulin reagents |
b) | Monospecific reagents — anti IgG, anti IgM and anti C3 |
c) | Monoclonal antibodies (with subclass specificity) |
2. | Enzyme-linked immunosorbent assays (ELISA) |
a) | Whole RBC |
b) | Isolated cell membranes |
c) | Purified antigen |
3. | Flow cytometry. Accurate assessment of subpopulations of RBC, with varying degrees of sensitisation. These techniques require refinement but are potentially the most sensitive. |
7.
K. Koike Z. X. Zhang Y. Sakamoto A. Miyake M. Inoue 《American journal of reproductive immunology (New York, N.Y. : 1989)》1998,39(3):217-222
PROBLEM: Cytokine-induced neutrophil chemoattractant (CINC) was reported to influence anterior pituitary hormone release. We recently found that Unkei-to, one of the Japanese Kampo medicines, stimulated CINC secretion by rat anterior pituitary cells and the pituitary folliculo-stellate (FS)-like cell line (TtT/GF). Therefore, the effect of Unkei-to on growth hormone (GH) secretion by rat anterior pituitary cells was investigated. METHOD OF STUDY: Dispersed normal anterior pituitary cells, the folliculo-stellate-like cell line TtT/GF, and the GH3 cell were used to test the effect of Unkei-to on GH secretion. In reconstitutive coculture experiments, TtT/GF cells were mixed with GH3 cells at a ratio (TtT/GF cells: GH3 cells) of 1:99. From this mixture, cells were seeded onto plates at a density of 104 cells/well and were cultured for 5 days. The cells were then used in the experiments. RESULTS: Unkei-to at 20 μg/ml significantly inhibited GH secretion by normal anterior ptuitary cells within 12 hr of incubation. In contrast Unkei-to stimulated GH secretion by GH3 cells in a time- and dose-dependent manner, suggesting that an accessory cell type was involved. To assess the contribution of CINC as a paracrine factor, an experiment using a reconstitutive coculture system was performed, and Unkei-to was found to inhibit GH secretion when GH3 cells were cocultured with TtT/GF cells. The addition of anti-CINC antibody to the reconstitutive coculture system antagonized Unkei-to-inhibited GH secretion. CONCLUSION: CINC, which was secreted from FS cells by Unkei-to, may be responsible for mediating the inhibitory effect of Unkei-to on GH secretion by rat anterior pituitary cells. 相似文献
8.
H. Albus J. A. Groot J. Siegenbeek van Heukelom 《Pflügers Archiv : European journal of physiology》1976,365(1):1-8
1. | A study has been made of the effect of serosally added sugars on the transmural potential difference and electrical resistance of the perfused goldfish intestine. |
2. | Addition of glucose at the serosal side resulted in a decrease of the transmural potential difference independent of the presence or absence of glucose at the mucosal side. The transepithelial resistance did not change. |
3. | The serosal glucose effect persisted in the presence of phlorizin at the mucosal side. |
4. | With the actively transported non-metabolized glucose analogue 3-oxy-methyglucose the same effects were observed as with glucose. |
5. | Replacement of NaCl by cholineCl, RbCl or LiCl at both sides of the intestine had a diminishing effect on the glucose evoked potentials and on the transepithelial conductance. |
6. | Phlorizin in concentrations lower than 10–4 M, at the serosal side did not influence neither the mucosal nor the serosal glucose effects. |
7. | Ouabain at the serosal side inhibited the serosal glucose effect and decreased the transepithelial conductance. |
8. | The results support the concept that sugar transport at the serosal side of the epithelial cell has features in common with the sodium-dependent sugar transport mechanism at the mucosal side. |
9.
Csaba Rusznak Jagdish L. Devalia Jiahua Wang Robert J. Davies 《Clinical reviews in allergy & immunology》1997,15(2):205-217
Conclusions Taken together, the findings of both epidemiological and laboratory-based studies provide evidence that exposure to air pollutants
generated from petrol and diesel-burning engines are likely to precipitate attacks of asthma and rhinitis, and possibly contribute
to the increase in prevalence of these disorders. The mechanisms by which pollutants exert their effects may be either indirect
(modulation of allergenicity of airborne allergens) or direct:
相似文献
1. | Increased epithelial damage and permeability; |
2. | Decreased ciliary activity; |
3. | Depletion of naturally occurring antioxidants; and |
4. | Release of proinflammatory cytokines and cell adhesion molecules, which orchestrate the functions of inflammatory cells, such as eosinophils, mast cells, and lymphocytes (Fig. 4). |
10.
AECA represent a new family of autoantibodies detectable in systemic autoimmune diseases. Different findings support their
poten-tial importance both from a diagnostic and a prognostic point of view:
On the other hand, AECA do not display an absolute cell specificity, being crossreactive, at least in part, with other cell
types and lack of disease specificity. Up to now, AECA determination are still matter of research but their clinical usefulness
in autoimmune diseases could increase when simpler assays for the detection will be available. 相似文献
1. | AECA do not seem to be a mere epiphenomenon; |
2. | Are not related to a polyclonal B-cell activation; |
3. | React with surface endothelial antigens; |
4. | Correlate with disease activity; |
5. | In some cases behave as an indirect marker of in vivo endothelial damage; |
6. | Correlate with disease activity; and |
7. | In vitro experiments support a possible pathogenetic role in sus-taining autoimmune vasculitis. |
11.
A. N. Brendsted 《Neuroscience and behavioral physiology》1976,7(3):266-270
1. | During the assembling of a mechanical toy from its parts by children aged 6–7 years, spatial synchronization of cortical potentials is strengthened. |
2. | When the skill is formed, the focus of maximal activity in children with a stereotyped form of activity is located in the inferior parietal regions; in children with variable activity it lies in the anterior zones of the brain. |
3. | During consolidation of the skill the number of interhemispheric correlations increases, evidence of an increase in the degree of paired activity in the work of the child's brain. |
4. | Differences in the topographic distribution of interhemispheric spatial synchronization of brain electrical activity depend on the character of problem solving activity. If the task is performed in a stereotyped manner, correlations are strongest in the left motor area and right inferior parietal region; in the case of variable performance, correlation is strongest in the left motor area and right frontal region. |
12.
T. V. El'tseva E. I. Adamskaya T. A. Peryshkova V. N. Babichev 《Neuroscience and behavioral physiology》1993,23(6):538-544
1. | A decrease in the level of activity of both motivational and copulatory components of sexual behavior was observed during the development of experimental diabetes following the administration of streptozotocin to rat males. |
2. | The concentration of LHRH in diabetic rats decreased in the ME [sic], and similar changes were recorded in both the PA and the MBH when it was determined in the synaptosomal fraction of the hypothalamus. |
3. | The concentration of nuclear E2 receptors was increased in the APA at the level of the hypothalamus, whereas the number of testosterone-binding sites did not differ from the values of the control group. |
4. | The level of LH and FSH in the blood of the rats did not change during the development of diabetes, the concentration of PRL and T decreased, and that of E2 increased. |
13.
O. V. Smirnova T. G. Vishnyakova V. B. Rozen 《Neuroscience and behavioral physiology》1990,20(1):51-56
1. | Administration of insulin does not significantly affect the level of SEBP in the livers of male rats. |
2. | Adrenalectomy and administration of dexamethasone do not cause any pronounced changes in the sexual differentiation of the SEBP content in the liver. |
3. | Administration of physiological doses of T3 produces a dose-dependent and reversible decrease in the level of SEBP in the livers of sexually mature male rats, and also decreases the degree of induction of this protein by androgens in the livers of females. |
4. | The action of T3 does not significantly depend on the sex hormones and pituitary factors. |
5. | Administration of STH raises the level of SEBP in the liver only in hypophysectomized males but not in intact or castrated males. |
14.
Greven K. Rudolph K. H. Hohorst B. 《Pflügers Archiv : European journal of physiology》1976,362(3):255-260
1. | Experiments to investigate the creep phenomena of the taenia coli were performed in hypotonic (207 mosm) and hypertonic (447 or 463 mosm) media, in the relaxed (Ca2+-depletion+verapamil) as well as in the contracted (K2SO4-depolarized) state. They were compared with earlier results in isotonic media. The samples were standardized with respect to their volume (weight) before the beginning of the experiment. |
2. | Neither in the relaxed, nor in the contracted state was there a statistically significant difference in mean total length observed within each test series after loading with 9928 dyn for 2000 s (about 33 min) in the different osmotic media. We define total length as unloaded initial lengthl o+initial pure elastic extensionl E+creep N. |
3. | In the contracted state the mean total lengths attained by elastic extension and creep are significantly greater than in the relaxed state in both hypotonic and isotonic media. The greater variance in the data for hypertonic solutions makes any statistical decision of this kind impossible. |
4. | The typical time course of creep (N) and particularly the hyperbolic dependance of N anddN/dt stated in an earlier paper could also be observed here under varied osmotic conditions. |
5. | The results suggest that the viscosity of the cell plasma is not significant for the time course and extent of creep in smooth muscles of vertebrates. Creep probably takes place in the solid structures of the cells: most particularly the contractile proteins may be involved. |
15.
K.-E. Grand M. Hara A. Bohle 《Virchows Archiv : an international journal of pathology》1976,370(4):297-305
Morphometrical and clinical investigations were performed in 34 patients with the so-called hypercellular form of focal glomerulosclerosis (FGS), i.e., a form showing clear diffuse mesangial hypercellularity beside focal sclerosis with the light microscope. This form was compared with focal glomerulosclerosis without remarkable mesangial hypercellularity, with mild mesangioproliferative glomerulonephritis (gn), as well as with normal kidneys.The results were as follows:
相似文献
1. | Morphometrically both the increase in relative mesangial volume as well as in mesangial cell count is statistically significant in the hypercellular form compared with the nonhypercellular form and with controls. Comparison with mild mesangioproliferative gn shows no difference. |
2. | Even the so-called nonhypercellular form contains more mesangial matrix and mesangial cells than the controls. |
3. | The frequency of the hypercellular form is higher in males and in older patients. |
4. | All of our patients with hypercellular FGS had at the time of biopsy manifested nephrotic syndrome. The frequency of additional clinical symptoms (hematuria, hypertension, renal insufficiency) corresponds with the nonhypercellular form, but is different in mild mesangioproliferative gn. |
5. | Therapeutic response and prognosis is worse in the hypercellular form. |
16.
(1) | The isolated rabbit ear was perfused via its artery and the venous outflow superfused a PGE-sensitive rat stomach strip or a PGF-sensitive rat colon. |
(2) | Injection of bradykinin intra-arterially into the ear produced a larger contraction of the rat stomach strip than the application of the same dose of bradykinin directly to the superfused muscle. |
(3) | This difference is explained as a release of PGE-like material by bradykinin, since indomethacin (infused i.a. into the ear) reduced the effect of the i.a. applied bradykinin. |
(4) | PGF-like material could not be detected in the venous effluent. |
(5) | ACh released only minimal amounts of PGE-like substance. |
(6) | Conclusion: The amount of PGE-like material released by bradykinin is large enough to sensitize the paravascular pain receptors in the rabbit ear for the attack of bradykinin. Therefore, inhibition of PG-synthesis (i.e. by indomethacin) or inhibition of the sensitizing action of E-type PGs (i.e. by polyphloretin phosphate) reduces the pain producing effect of bradykinin. Since ACh releases only minimal amounts of E-type PGs, its effect is reduced only to a minimal extent by indomethacin or polyphloretin phosphate. |
17.
Romain A. Pauwels 《Clinical reviews in allergy & immunology》1989,7(3):235-243
The airways have a repertoire of defense mechanisms against stimuli entering the tracheobronchial tree. Bronchial asthma can
be regarded as an exaggerated airway response to different exogenous stimuli. There is indirect evidence that asthmatics form
a heterogeneous population characterized by an increased responsiveness in one or more of these airway defense mechanisms.
Furthermore, human investigations and animal experiments suggest that both environmental and genetic factors operate at these
different levels. The aim of the present paper is to review the evidence that genetic factors control the airway response
to exogenous stimuli and correlate these observations with the evidence that genetic factors are involved in the pathogenesis
of human bronchial asthma.
The airways are controlled by a complex network of defense mechanisms that aim at guarding the normal physiological function
of the airways, i.e., the conduction and conditioning of air (1,2). The airway defense mechanisms can be divided roughly in the following more or less interwoven aspects
相似文献
1. | Reflex bronchoconstriction either by local axon reflexes, or vagal reflexes via the central nervous system; |
2. | Increase in mucus production and mucociliary clearance; |
3. | Cough; |
4. | Inflammation involving different cell types, such as the airway epithelial cells, macrophages, mast cells, and the influx of secondary cells such as neutrophils, eosinophils, and platelets; and |
5. | Immunological response resulting in a more rapid and a more intense inflammatory and possibly also reflex response. |
18.
F. V. Kopytova 《Neuroscience and behavioral physiology》1976,7(4):339-347
1. | Responses of dorsal hippocampal neurons were investigated during combinations of an acoustic stimulus with a direct current (anode), stimulating the cell through the recording microelectrode. Of the 45 cells, 22% formed conditioned responses of activation or inhibitory types which corresponded with the character of the reinforcing agent. Cells not responding to the stimuli did not form temporary connections. Approximately half of the conditionally responding neurons formed extinction and differentiation to an unreinforced stimulus. |
2. | During periodic presentation of combinations of acoustic and electrical stimulation 30% of the 25 cells formed conditioned responses to time. Significant trace reproduction of conditioned responses was observed during 10 to 12 omissions of the stimuli. Cells forming ordinary conditioned responses could produce conditioned responses to time also. They were formed more rapidly. |
3. | Prolonged periodic presentation of the acoustic stimulus leads to rhythm binding of the previous stimulation. These responses differ from conditioned responses to time in their short duration, the absence of spontaneous recovery of the responses, and their occurrence within a definite time interval. |
4. | It is suggested that the characteristics discovered during the formation of simple temporary connections and observed in various model situations in neurons belonging to different brain structures are common to many conditioned-reflex acts. |
19.
K. Wegener H. Wesch H. Kampmann 《Virchows Archiv : an international journal of pathology》1976,371(2):131-143
The subjects of investigation were 13 dead thorotrast patients, 10 male, 3 female, with ages ranging from 45 to 79 years. Two thousand organ and tissue specimens were investigated by means of autopsy and by both microscopic-autoradiographic and neutron activation analysis in order to detect late effects and to determine on approximate mean concentration of 232Th (mg per g of tissue).A comparison between late effects and concentrations of the dye medium led to the following conclusions:
相似文献
1. | 232Th is, after intravascular injection, deposited in all organs and tissues of the human body. |
2. | The highest mean concentrations are shown in the spleen, liver, bone marrow, and lymph nodes. |
3. | The distribution of 232Th is inhomogeneous in all organs and tissues. The variations of maximum and minimum concentration lie around factor 2.2×100–2.4×105. |
4. | Late effects occur only in spleen, liver, lymph nodes, and bone marrow, but not in organs and tissues that show a mean concentration of 232Th under 10–1 mg per g tissue. |
5. | It is highly probable that tumors of thorotrast patients in organs other than spleen, liver, lymph nodes, and bone marrow are not caused by deposition of 232Th or ThO2. |
20.
Y. Shinoda A. P. Arnold H. Asanuma 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1976,26(3):215-234
Branching patterns of single corticospinal (CS) neurons were studied in the cat by activating these neurons antidromically from various regions of the spinal cord.
相似文献
1. | One hundred and ninety-three neurons were activated antidromically by microstimulation in the gray substance of the cervical cord and the majority of them were found in the forelimb area of the pericruciate cortex. |
2. | Branches to the lower levels of the spinal cord were found for 30% of the neurons projecting to the cervical gray matter. |
3. | The remaining 70% sent axons only to the cervical gray matter and some of them sent multiple branches to several segments in the cervical cord. |
4. | Only a few CS neurons located outside of the forelimb area could be activated from the cervical cord, but all of them also sent branches to the lower levels of the spinal cord. Neurons projecting to both the cervical cord and the lower levels were intermingled in the cortex with those projecting only to the cervical cord. |
5. | CS neurons activated from a given area of the cervical cord were often clustered together in a small area of the cortex, although some of these CS neurons sent their other branches to other parts of the spinal cord and neurons projecting to other parts were also intermingled among them. |
6. | The functional significance of multiple axonal branching of CS neurons is discussed in relation to cortical motor functions. |