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The regulation of heat shock protein 90 kDa (hsp90) by estradiol was analyzed in the rat ventromedial hypothalamus (VMH) and uterus by one-dimensional gel electrophoresis/Western blots. Protein from VMH and uterus (35 micrograms/sample) was resolved on 8% acrylamide gels, transferred to polyvinyldifluoride filters, and processed for immunoblotting using an anti-hsp90 antibody. Hsp90-specific bands were visualized on film using enhanced chemiluminescence and quantitated using a laser scanning densitometer. Hsp90 protein levels were significantly elevated in VMH at 12 h (p less than 0.01), and in uterus at 18 h (p less than 0.05) following estradiol injection (10 micrograms, s.c.). Immunocytochemical analysis for hsp90 localization by cell types showed that, in brain, hsp90 immunoreactivity was primarily neuronal. In the uterus, hsp90 immunoreactivity was most evident following treatment with estradiol, and was found primarily in the glandular epithelia; staining was less prominent in myometrium, stroma, and in the luminal epithelium. Thus, increased hsp90 levels may mediate some cellular responses to estrogen in specific cell types in both uterus and brain. 相似文献
4.
In the lateral longissimus muscle (LL) of ovariectomized, female rats anesthetized with low surgical doses of urethane (1.0 g/kg), cutaneous reflexes with similar EMG and response patterns could be elicited from CNS-intact rats and from rats 24 h after complete thoracic spinal cord transection. The probability of eliciting a response to contralateral cutaneous nerve stimulation alone is much lower in rats with complete spinal transections compared to CNS-intact rats. For both CNS-intact and spinal-transected rats, responses to ipsilateral cutaneous nerve stimulation had a shorter latency and required significantly less current on average than responses to contralateral stimulation. The respective currents for eliciting threshold responses to ipsi- and contralateral stimulation are less for CNS-intact than spinal-transected rats. For both CNS-intact and spinal-transected rats, responses to bilateral cutaneous nerve stimulation were inconsistent in the same animal from run to run. With the variability of response at this anesthetic level, no consistent effects of progesterone (acute, i.v.) or estrogen (acute, i.v. and pretreatment, s.c.) were observed in spinal-transected rats. Intravenous progesterone reduced early, unilateral responses in CNS-intact rats anesthetized with 1.0 g of urethane/kg. For both CNS-intact and spinal-transected rats, additional anesthesia during EMG recording produced a gradual decline in response magnitude which could be recovered with a modest increase in stimulus intensity. However, spinal-transected rats appear to require less anesthesia to reduce comparable responses. The results suggest that supraspinal input is especially effective for facilitating contralateral cutaneous reflexes in back muscles, whereas it contributes more equally with afferent input and segmental circuitry to the efficacy of ipsilateral cutaneous reflexes. 相似文献
5.
M Schwanzel-Fukuda S Abraham K L Crossin G M Edelman D W Pfaff 《The Journal of comparative neurology》1992,321(1):1-18
Contact between the developing forebrain and the ingrowing central processes of the olfactory, vomeronasal and terminal nerves is preceded by a migration of neural cell adhesion molecule (NCAM)-immunoreactive cells from the epithelium of the olfactory pit and the formation of an NCAM-immunoreactive cellular aggregate in the mesenchyme between the olfactory pit and the forebrain. The axons of the olfactory, vomeronasal, and terminal nerves, also NCAM-immunoreactive, grow into the cellular aggregate, which as development proceeds, becomes continuous with the rostral tip of the forebrain. The lateral and more rostral part of the cellular aggregate receives the ingrowing axons of the olfactory nerves and becomes the olfactory nerve layer of the olfactory bulb. The medial, more caudal part receives the central processes of the vomeronasal and terminal nerves. The vomeronasal nerve ends in the accessory olfactory bulb. The central processes of the terminal nerve end in the medial forebrain. Luteinizing hormone-releasing hormone (LHRH)-immunoreactive neurons, like the vomeronasal and terminal nerves, originate from the medial part of the olfactory pit. These LHRH cells migrate into the brain along and within a scaffolding formed by the NCAM-immunoreactive axons of the vomeronasal and terminal nerves, and they are never seen independent of this NCAM scaffold as they cross the nasal lamina propria. The results suggest that: (1) NCAM is likely to be necessary for scaffold formation, and (2) the scaffold may be essential for the subsequent migration of LHRH neurons into the brain. Because they aggregate, migrating LHRH-immunoreactive neurons, on which we did not detect NCAM immunoreactivity, may interact via other cell adhesion molecules (CAM). Inasmuch as the interaction between the LHRH-immunoreactive neurons and the NCAM-immunoreactive scaffold is heterotypic, the possibility of a heterophilic (NCAM to other CAM) interaction is not ruled out. These findings focus our attention on the functional role of NCAM in this migratory system. 相似文献
6.
The paper reports on acylaminoalkylbenzenesulfonamide derivatives with special heterocyclic acyl substituents. The compounds are characterized by an oxygen atom in ortho position to the carboxamide group of the heterocyclic acyl moiety. Several compounds show blood glucose lowering activities in animals similarly to glibenclamide. 相似文献
7.
The efficiency of preoperative laboratory screening of normal, healthy patients was investigated. Preoperative test results of 1311 consecutive patients were collected. Data on haemoglobin, serum potassium, serum creatinine and serum ALAT were routinely obtained. 736 patients were classified by history and physical examination as normal healthy persons not having any systemic disorder. In this group of patients no clinically relevant abnormal laboratory results were found under the age of 60 years. In the group of 60 years and older a significant number had elevated serum creatinine values. 相似文献
8.
L. -M. Kow D. W. Pfaff 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,67(1):93-99
Summary Electrical activity of neurons in rat hypothalamic ventromedial nucleus was recorded in tissue slices, to investigate central neural mechanisms underlying reduction of food intake caused by TRH and its metabolite, cyclo(His-Pro) [cHP]. Application of TRH had two actions: stimulation of neuronal activity, which was desensitized on closely repeated applications; and modulation of neuronal responses to neurotransmitters, even in the absence of the stimulatory action. The neuromodulatory but not the direct stimulatory action could also be achieved by cHP. The neuromodulatory action is more likely to be a neural mechanism underlying the inhibition of feeding, while other biological functions, unique to TRH, may depend on direct stimulation. In this way, TRH could achieve different biological results through different modes of action on hypothalamic neurons. 相似文献
9.
J. M. Rothfeld J. F. Hejtmancik P. M. Conn D. W. Pfaff 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,69(1):113-118
Summary The slow potential change (spc) accompanying spreading depression (SD) was studied in rats and in a seizure-sensitive strain of Mongolian gerbil under three different experimental paradigms, each involving the use of naloxone. Gerbils undergoing electroconvulsive shock treatment displayed SD during the post-ictal phase, which was blocked by the intraperitoneal (i.p.) administration of naloxone (20–50 mg kg-1). Topical application of naloxone to the exposed cortex of the anaesthetized gerbil and rat blocked the spc of SD evoked by KCl. Microiontophoretic ejection of naloxone during extracellular recordings reversed cell refractoriness following the spc, demonstrated by the observation of a maintained sensitivity to iontophoretic pulses of glutamate. The results suggest a possible involvement of naloxone-sensitive processes in the mechanism responsible for cortical SD. 相似文献
10.
Electrical stimulation in the mesencephalic central gray (CG) and adjacent subtectum through chronically implanted electrodes in free-moving estrogen-primed ovariectomized female rats elicited a rapid and large facilitation of the lordosis reflex in response to either male mounts or manula cutaneous stimuli. Unilateral stimulation was sufficient for this effect. The facilitation increased in a graded manner to increased stimulus intensity, and was optimally evoked by stimuli delivered at 50--150 Hz. Facilitation disappeared rapidly following the end ot electrical stimulation, and within 15 min, reflex performance returned to the prestimulation level. Lordosis facilitation appeared when no aversive responses occurred; stimulation with comparable parameters at the lateral edge of CG or in the mesencephalic reticular formation often resulted in postural changes or aversive responses but was not able to facilitate lordosis. Lordosis refelx facilitation was probably mediated by projections descending from neurons in and around the CG, and represents stimulation of a functional link between ascending somatosensory and descending motor systems for the control of lordosis behavior. 相似文献