m-Octopamine: Normal Occurrence with p-Octopamine in Mammalian Sympathetic Nerves

The development of a radiochemical enzyme assay for p-octopamine in 1969 led to its identification in a large number of invertebrate nerve systems and in mammalian sympathetic nerves. The original method by which p-octopamine was measured has now been found to be nonspecific; however, modifications of this procedure can determine both m- and p-octopamine. We recently developed a new specific method for the unequivocal identification and quantitative determination in tissue of the six octopamine and synephrine isomers. With this method--negative chemical ionization gas chromatography-mass spectrometry--the more physiologically active m-octopamine has been found in association with p-octopamine in 10 organs of the rat. m-Octopamine is present in concentrations equal to those of p-octopamine in heart, spleen, and liver and in concentrations from 30 to 60% of p-octopamine in adrenals, vas deferens, brain, kidney, large intestine, bladder, and lungs. In vivo inhibition of monoamine oxidase markedly increased the concentrations of both m- and p-octopamine in all organs examined. Both amines were virtually absent from all organs except the adrenals following chemical sympathectomy with 6-hydroxydopamine, thereby establishing that m- and p-octopamine are localized within sympathetic nerve endings.     

Culture of intramural cardiac ganglia of the newborn guinea-pig

Summary The present study describes the ultrastructure of non-neuronal cells and their interrelationships with intracardiac neurones present in cultures dissociated atria and interatrial septum from newborn guinea-pig. When compared with the in situ preparation, most of these features in culture were similar to those observed in situ, but some differences were also apparent. Both mature and immature Schwann cells were observed in culture, and as in situ, the latter were closely associated with intracardiac neurones, whilst the former were more widely separated. The ultrastructure of satellite cells was more variable in culture than in situ: three general types were distinguished on the basis of their 10-nm filament content. This variation could be due to conditions of culture. Interstitial cells were present in culture and closely resembled those described in situ, although there was less space between cultured interstitial cells and their associated cells. Many fibroblasts, some myoblasts and a few mast cells were also found in the culture preparations.     

Neurotensin interacts with carbachol, secretin, and caerulein in the stimulation of the exocrine pancreas of the rat in vitro

In the present investigation the effect of neurotensin on pancreatic secretion of isolated pancreatic lobules from the rat was examined. We found a dose- and time-dependent stimulation of amylase release beginning with a concentration of 10(-9) M neurotensin. This response was potentiated by the cholinergic agonist carbachol, the gastrointestinal peptide secretin, and the CCK analogue caerulein. As we found neurotensin-immunoreactive nerves within the pancreas and as neurotensin-like immunoreactivity is present in the circulation (found previously), neurotensin may well be a further peptide taking part in the regulation of exocrine pancreatic secretion either as a hormone or a neurotransmitter. Neurotensin would then cooperate with cholinergic mechanisms, secretin, and CCK.     

Catabolic Regulation of the Expression of the Major Myelin Glycoprotein by Schwann Cells in Culture

Previous studies have suggested that neonatal Schwann cell cultures deprived of axonal contact do not express components of the myelin membrane, including the major myelin glycoprotein, P0. In contrast, Schwann cells from permanently transected, adult nerve exhibit continued biosynthesis of P0 after culture, suggesting that the ability to express the myelin glycoprotein may depend on the degree of cellular differentiation. To examine further the ability of Schwann cell cultures to express P0 as a function of age, we have performed precursor incorporation studies on endoneurial explants from 4- to 12-day-old rat sciatic nerves after 5 days in culture. The data reveal that explants from 12-day-old animals synthesize detectable levels of this integral myelin protein when assayed by [3H]mannose incorporation, even though there is no apparent myelin assembly in the cultures. Pulse-chase analysis of cultures from 12-day-old rats demonstrates that [3H]mannose-labeled P0 is substantially degraded within 3 h. This catabolism largely can be prevented by the addition of swainsonine, ammonium chloride, or L-methionine methyl ester to the pulse-chase media. The former agent alters oligosaccharide processing whereas the latter two compounds inhibit lysosomal function. The P0 synthesized by the 12-day explant cultures following the addition of swainsonine is readily fucosylated, implying that the protein has progressed at least as far as the medial Golgi before its exit and subsequent catabolism. If cultures from 4-, 6-, and 8-day-old animals are analyzed for P0 biosynthesis by [3H]mannose incorporation in the presence of swainsonine, detectable levels of the glycoprotein are seen.(ABSTRACT TRUNCATED AT 250 WORDS)     

伤害性刺激和非伤害性刺激对大鼠丘脑后核神经元电活动的影响

用微电极细胞外记录的方法,观察内脏痛、躯体痛和触觉刺激对大鼠丘脑后核(PO)中770个神经元电活动的影响,其中305(38.3％)个对伤害性刺激起反应,103(13.4％)个对触觉刺激起反应。对伤害性刺激反应的神经元中多数对躯体痛和内脏痛刺激均起反应且反应形式相同,少数反应不同或相反,对触觉刺激反应的神经元中多数也对两种伤害性刺激均起反应,只对触觉刺激反应的神经元很少。     

Ciliary Neurotrophic Factor (CNTF) Genotypes and CNTF Contents in Human Sciatic Nerves as Measured by a Sensitive Enzyme-Linked Immunoassay

Abstract: To study the level of ciliary neurotrophic factor (CNTF) in human nervous tissues, we developed a sensitive enzyme-linked immunoassay using a specific antibody against human CNTF. This method allowed us to detect as little as 0.3 ng/ml of human CNTF with good linearity and accuracy. Using this method, CNTF levels were determined in human sciatic nerves obtained at autopsy from 21 amyotrophic lateral sclerosis (ALS) patients and 48 subjects who had died of other neurological diseases. CNTF genotypes were also determined. The results indicated that CNTF levels were high in the normal homozygotes and approximately halved in the heterozygote subjects. There was, however, no significant difference in CNTF levels in the sciatic nerves between ALS and other neurological disease patients, indicating that the CNTF level was mainly determined by its genotypes and that the level in the sciatic nerves was not reduced in ALS patients.     

迷走神经背核的研究进展

迷走神经背核（ＤＭＶ）是一个重要的内脏运动核团和内脏感觉核团。ＤＭＶ与中枢及外周存在广泛的纤维联系。ＤＭＶ和孤束核、最后区一起构成了“迷走感觉运动中枢”。ＤＭＶ存在神经－体液回路,使ＤＭＶ神经元可以直接感受外周血及脑脊液中的信息。ＤＭＶ含乙酰胆碱、儿茶酚胺、神经肽类等多种递质及相应受体。ＤＭＶ参与中枢调节胃肠、心血管及内分泌等生理功能。     

心率与血压的变异性：分析方法,生理意义及其应用

本文回顾了关心回顾变异性及血压变异性的最新进展。在分析方法方面介绍了单一生理变量多变量系统的线性分析技术及其主要结果。对ＨＲＶ／ＢＰＶ谱的生理意义及其应用问题,也进行了回顾了评述。     

Immunochemical study of galanin in the cat digestive tract and autonomic ganglia

The presence of galanin was examined in the cat gut and related autonomic nervous structures using radioimmunoassay (RIA) and high performance liquid chromatography (HPLC). In the gut wall, the concentration of galanin-like immunoreactivity (GAL-LI) was assayed separately in the muscular layers with the nervous plexuses and in the mucosa and ranged from 0.35 to 0.55 pmol/g wet tissue. In the autonomic nervous structures, GAL-LI concentrations ranged from 0.22 (thoracic spinal ganglia) to 0.81 (inferior mesenteric ganglion) pmol/g wet tissue. The presence of galanin was checked by HPLC in the antrum, intestine, and colon. HPLC of extractable material revealed a major peak coeluting with the synthetic porcine peptide and minor earlier peaks representing likely different molecular forms of galanin. Our study strengthens the notion that galanin acts in nervous control of the cat gut functions.     

Distribution of PACAP (pituitary adenylate cyclase-activating polypeptide)-like and helospectin-like peptides in the teleost gut

Pituitary adenylate cyclase-activating polypeptide (PACAP) and helospectin are two vasoactive intestinal polypeptide (VIP)-related neuropeptides that have recently been demonstrated in the mammalian gut; the aim of this study was to reveal their occurrence and localisation in the gastrointestinal tract, swimbladder, urinary bladder and the vagal innervation of the gut of teleosts, using immunohistochemical methods on whole-mounts and sections of these tissues from the Atlantic cod, Gadus morhua and the rainbow trout, Oncorhynchus mykiss. Both PACAP-like and helospectin-like peptides were present in the gut wall of the two species. Immunoreactive nerve fibres were found in all layers but were most frequent in the myenteric plexus and along the circular muscle fibres. Immunoreactivity was also demonstrated in nerves innervating the swimbladder wall, the urinary bladder and blood vessels to the gut. Immunoreactive nerve cell bodies were found in the myenteric plexus of the gut and in the muscularis mucosae of the swimbladder. In the vagus nerve, non-immunoreactive nerve cells were surrounded by PACAP-immunoreactive fibres. Double staining revealed the coexistence of PACAP-like and helospectin-like peptides with VIP in all visualized nerve fibres and in some endocrine cells. It is concluded that PACAP-like and helospectin-like peptides coexist with VIP in nerves innervating the gut of two teleost species. The distribution suggests that both PACAP and helospectin, like VIP, are involved in the control of gut motility and secretion.