Effect of lithium chloride on the neurosecretory system of the rat hypothalamus

The response of the hypothalamic-pituitary neurosecretory system (HPNS) of rats to a single and repeated injection (200 mg/kg each time) of lithium chloride was studied by quantitative cytochemical analysis. The response of the HPNS was found to depend directly on the dose of lithium given and to consist of activation of synthesis and liberation of neurosecretion after a single dose of LiCl or inhibition of hormone formation in the hypothalamus and exhaustion of the reserves of neurosecretion in the neurohypophysis after a course of injections. In the recovery period (7–30 days after stopping the course of injections of LiCl) the previous state of the HPNS was gradually restored.Laboratory of General Physiology, Institute of Pharamacology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 1, pp. 32–34, January, 1977.     

萘哌地尔对慢性心力衰竭患者神经内分泌的影响

目的: 观察萘哌地尔治疗慢性心力衰竭(CHF)患者时对神经内分泌的影响.方法: 放射免疫法测定47例CHF患者(CHF组)与24例健康者(对照组)血肿瘤坏死因子-α(TNF-α)、白细胞介素-1(IL-1)、白细胞介素-6(IL-6)、内皮素-1(ET-1)、肾上腺髓质素(Adm)、神经肽Y(NPY)、降钙素基因相关肽(CGRP)、A型利钠肽(ANP)、B型利钠肽(BNP)和C型利钠肽(CNP)的水平,超声心动图测定左室射血分数(LVEF).CHF组再随机分为:常规治疗组(A组)24例,给予常规心衰治疗;萘哌地尔治疗组(B组)23例,在A组药物治疗基础上加服萘哌地尔,1月后重复上述测定.结果: (1)CHF患者血TNF-α,IL-1,IL-6,ET-1,Adm,NPY,ANP,BNP,CNP水平均显著高于对照组(P＜0.01),而CGRP水平显著低于对照组(P＜0.01);(2)A组和B组治疗前后比较,血TNF-α,IL-1,IL-6,ET-1,Adm,NPY,ANP,BNP, CNP水平均显著降低(P＜0.01),而CGRP水平增高(P＜0.01);(3)B组治疗后与A组治疗后比较,TNF-α,ET-1,ANP,BNP降低更明显(P＜0.05), NPY水平下降更显著(P＜0.01), 而CGRP水平升高更明显(P＜0.05), NYHA分级改善更明显(P＜0.05),但IL-1,IL-6,Adm,CNP和LVEF无显著差异(P＞0.05).(4)LVEF与TNF-α,IL-6,ET-1,BNP呈负相关(P＜0.05).结论: TNF-α,IL-1,IL-6,ET-1,Adm,NPY,CGRP,ANP,BNP和CNP可能与CHF发生发展有关,萘哌地尔治疗可能进一步降低CHF患者TNF-α,ET-1,ANP,BNP,NPY水平和提高CGRP水平并改善临床症状.     

BK Polyomavirus Interstitial Nephritis in a Renal Allograft Recipient

Human polyomavirus (PV) interstitial nephritis has recently been recognized as a cause of severe renal allograft dysfunction. It occurs in immunosuppressed patients after reactivation of the latent virus PV type BK (BK virus) in the renal epithelium. BK disease is defined as a morphologically manifest renal infection with cytopathic signs accompanied by varying degrees of interstitial inflammatory cell infiltrates and functional impairment. It is also identified by the presence of cells containing viral inclusion bodies (decoy cells) in the urine. The authors report a case of BK PV interstitial nephritis in a 36-year-old renal allograft recipient. Under light microscopy the chief diagnostic indicator was detection of intranuclear viral inclusions, which were found exclusively in tubular epithelial cells. Cells with viral changes were often enlarged with nuclear atypia and chromatin basophilia. Widespread interstitial plasma cell infiltrates associated with tubulitis were present. Intranuclear paracrystalline arrays of virus particles 35-38 nm in diameter were present as characteristic ultrastructural indicators. Urine samples revealed decoy cells with ground-glass-type intranuclear inclusions positive for BK virus by electron microcopy.     

Tumors of the Endocrine/Neuroendocrine System: An Overview

For the sake of discussion, the markedly diversified tumors of the endocrine/neuroendocrine system are classified as those originating in classic epithelial endocrine organs (eg, adrenal cortical adenomas), from the diffuse endocrine cells (eg, jejunal carcinoid tumors), or from clusters of these cells (eg, islet cell tumors); and those arising from neurosecretory neurons (eg, neuroblastoma) or paraganglia (eg, carotid body tumor). Although traditional transmission electron microscopy is useful for identifying neurosecretory or endosecretory granules as such, with few exceptions (eg, insulin-containing granules with a complex paracrystalline core) it is not possible to ascribe a granule type (size, shape, or ultrastructure) to a distinct nosologic entity or secretory product because of their overlapping fine structures in different cell types. Immuno-electron microscopy methods utilizing colloidal gold-labeled secondary antibodies can be used to localize virtually any antigen (peptide or neuroamine) to a specific neurosecretory or endosecretory granule or other cell structure. General endocrine/neuroendocrine cell markers such as neuron-specific enolase, the chromogranins, and synaptophysin are useful in identifying neuroendocrine differentiation in a neoplasm using routine immunohistochemical procedures. The current relevance of the APUD concept of Pearse as well as the biologic importance of endocrine/neuroendocrine secretory products such as bombesin and insulinlike growth factors also are discussed.     

Identification and distribution of a proctolin-like neuropeptide in the nervous system of the gypsy moth, Lymantria dispar, and in other Lepidoptera

Although the neuropeptide proctolin has important functions in many arthropods, it is reported to be absent in Lepidoptera. Its possible occurrence in these insects was reinvestigated by bioassays of HPLC fractions and immunocytochemistry. A proctolin-like substance was recovered from the frontal and subesophageal ganglia of Lymantria dispar. This substance has the same chromatographic retention time as proctolin; enzymatic degradation indicates that it is a peptide; it is bound by proctolin antisera; and thus it is indistinguishable from authentic proctolin. A small subpopulation of proctolin-like immunoreactive (PLI) neurons was stained in the larval CNS of L. dispar, Manduca sexta, Trichoplusia ni, Galleria mellonella, and Vanessa cardui. Most prominent of these cells are median neurosecretory neurons in the brain, paired neurons in the frontal ganglion, two clusters of neurons in the subesophageal ganglion, paired lateral neurons in the thoracic ganglia, and dorsomedial neurons in the abdominal ganglia. Also, varicose PLI axons are found in the corpora cardiaca and perivisceral organs. In L. dispar, PLI cells also were found in the corpora cardiaca. The results of this study indicate that proctolin is of general occurrence in the Lepidoptera, that it has an important role in the stomatogastric nervous system, and that it may be released as a local neurohormone from various neurohemal organs.     

Substance P-, FMRFamide-, and gastrin/cholecystokinin-like immunoreactive neurons in the thoraco-abdominal ganglia of the flies Drosophila and Calliphora.

Immunocytochemical analysis of the thoraco-abdominal ganglia of the flies Drosophila melanogaster and Calliphora vomitoria revealed neurons displaying substance P- (SPLI), FMRFamide-(FLI), and cholecystokinin-like (CCKLI) immunoreactivity. It could be demonstrated that a number of neurons contain peptides reacting with antisera against all the three types of substances, others were either FLI or CCKLI alone. No neurons displayed only SPLI. Instead, the total number (about 30) of SPLI neurons constitute a subpopulation of the FLI/CCKLI neurons. Many of the identifiable immunoreactive neurons seem to be homologous in the two fly species. One set of six large neurons, termed ventral thoracic neurosecretory neurons (VTNCs), are among those that are SPLI, FLI, and CCKLI in both Drosophila and Calliphora. With the present immunocytochemical technique, the detailed morphology of the VTNCs could be resolved. These neurosecretory neurons supply the entire dorsal neural sheath of the thoraco-abdominal ganglia with terminals, thus forming an extensive neurohaemal area. The VTNCs also have processes connecting the thoracic neuromeres to the cephalic suboesophageal ganglion, as well as extensive arborizations in the thoracic ganglia, suggesting an important role in integrating and/or regulating large portions of the central nervous system, in addition to their neurosecretory function. Most of the other SPLI, FLI, and CCKLI neurons in the thoraco-abdominal ganglia seem to be interneurons. However, there are four FLI neurons that appear to be efferents innervating the hindgut and a few abdominal FLI and CCKLI neurons may be additional neurosecretory cells. From the present study it appears as if neuropeptides related to substance P, FMRFamide and CCK have roles as neurotransmitters/neuromodulators and circulating neurohormones in Drosophila and Calliphora.     

α-Adrenergic activation of rat hypothalamic supraoptic neurons maintained in vitro

Extracellular recordings from 141 rat supraoptic nucleus neurons maintained in vitro in a perfused hypothalamic explant indicated that the excitability of 85% of cells was enhanced by the addition of 10–200 μM norepinephrine (NE) and the α-agonist methoxamine (MOXY), but not by isoproterenol, to the perfusion medium or by pressure application. Similar responses were observed from 7 cells maintained in synaptic isolation in medium containgng 15 mM Mg²⁺. At the lowest effective concentration (10 μM), NE and MOXY induced bursting activity without an overall increase in firing frequency; at higher concentrations an initial increase in firing frequency was followed by the appearance of phasic activity patterns. The actions of NE and MOXY were reversibly blocked by administration of the α-adrenergic antagonists phenoxybenzamine (1–10 μM), yohimbine (> 10 μM) and irreversibly blocked by prazosin (10 nM−1 μM). These observations suggest that NE has a predominatly facilitatory role to enhance the excitability and promote bursting activity in supraoptic neurosecretory neurons through an α-1 adrenoreceptor mechanism.     

Caudal neurosecretory system synaptic morphology following deafferentation: An electron microscopic degeneration study

The caudal neurosecretory system of Poecilia sphenops (molly) is an isolated population of neurosecretory cells located in the caudal most aspect of the teleost spinal cord. The structure of this neuroendocrine system is favorable for studies on the synaptic control of neurosecretory mechanisms. Little is known about the detailed synaptology of the system. Morphological and electrophysiological reports have shown that the caudal neurosecretory system is linked to higher brain centers by descending spinal projections. To examine the synaptology of the descending synaptic input, surgical deafferentation was performed by microsuction removal of a segment of spinal cord rostral to the caudal system. The degeneration of axon terminals was studied at various times following deafferentation and compared to control synaptology. Based on vesicle content and morphology, three axon terminal types were found in the caudal neurosecretory system. These terminals formed axosomatic, axodendritic, and axoaxonic synaptic contacts. Following deafferentation, axon terminals with dense-cored vesicles and boutons with round clear vesicles degenerated as evidenced by the electron dense dark reaction and the electron lucent reaction respectively. This suggested that at least two different types of axon terminals arise from the descending projection to the caudal neurosecretory system and that two different neurotransmitters may be influencing the neurosecretory activity of these cells.     

Spatiotemporal patterns of IGF-like peptide expression in the silkmoth Bombyx mori predict its pleiotropic actions

In vertebrates, insulin-like growth factors (IGFs) play important roles in the regulation of growth and development. Although the principal source of circulating IGFs is the liver, IGFs are also secreted by many other tissues, functioning locally through paracrine/autocrine mechanism. In the silkmoth Bombyx mori, Bommo-IGF-like peptide (BIGFLP) is the functional counterpart of vertebrate IGFs and is mainly produced by the fat body, a functional equivalent of the vertebrate liver and adipocytes. However, its production by other tissues has not yet been analyzed. In this study, we systematically surveyed the BIGFLP-producing tissues and stages by means of immunohistochemistry, in situ hybridization and real-time quantitative RT-PCR, showing that BIGFLP is also produced by the neurosecretory cells in the brain, ovariole sheath and testis sheath, in a stage-specific manner. The BIGFLP-producing cells in the brain were identical to the cells that produce bombyxins, insulin-like peptides of B. mori, but the temporal expression patterns of both peptides were totally different. The BIGFLP gene expression in the sheaths of ovariole and testis were induced by ecdysteroid in vitro, similar to the expression in the fat body. A very high BIGFLP immunoreactivity was also found in the pupal nephrocytes, a functional equivalent of the glomerular podocytes in the vertebrate kidney, without the expression of the gene, suggesting that circulating BIGFLP is taken up and degraded by these tissues. Based on the present observations, the physiological functions of BIGFLP in B. mori development are discussed.     

运动对慢性应激所致抑郁样老年大鼠行为异常及神经内分泌的影响

目的探讨运动对慢性不可预见温和应激(CUMS)抑郁老年大鼠行为学及血清皮质醇和促肾上腺皮质激素(ACTH)浓度的影响。方法 50只雄性老年SD大鼠随机分为对照组、CUMS组、低强度跑台运动训练(LITT)组、中等强度跑台运动训练(MITT)组、高强度跑台运动训练(HITT)组。采用CUMS加孤养复制老年大鼠抑郁模型。采用旷场实验得分和强迫游泳实验评价各组大鼠行为学改变,分别采用ELISA和放射免疫方法检测血清皮质醇、ACTH浓度。结果与对照组比较,CUMS组大鼠血清皮质醇和ACTH浓度增高(P<0.01);与CUMS组比较,LITT组、MITT组和HITT组大鼠水平运动和垂直运动增多、清理次数增加,中央格停留时间缩短,血清皮质醇和ACTH浓度降低(P<0.05,P<0.01)。结论 CUMS可使老年大鼠行为及内分泌发生异常改变,引起抑郁;适度的运动可调节CUMS引起的下丘脑-垂体-肾上腺轴功能亢进,具有抗抑郁及降低抑郁程度的作用。