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Quarter-micron serial sectioning is a technique useful for 3-D analyses in which light microscopical resolution is not sufficient and the maximal resolution of the electron microscope is not necessary. We propose that the technique described here is advantageous for many current electron microscopic studies in which ultrathin sections are commonly used. In particular, the sections are sturdier; they yield high-contrast images; they contain, per section, more information about the third dimension, information that can be retrieved through stereoscopy; and, when it comes to 3-D reconstruction from serial sections, less sections are needed to reconstruct tissue elements contained in a bloc of a given size. Compared to thicker sections, quarter-micron sections yield images of acceptable readability.

Electrophoretically homogeneous preparations of catalytic subunit (C) of cAMP-dependent protein kinase isolated according to two different procedures from holoenzyme type I and type II from rabbit and from holoenzyme type II from rat skeletal muscle and from bovine cardiac muscle can be separated on carboxymethyl cellulose or on a Mono S column (Pharmacia) by salt gradient elution into two enzymatically active peaks called A and B, which do not interconvert on rechromatography. Cochromatography of peak A fractions or of peak B fractions derived from both holoenzymes respectively yields single enzyme peaks in each case, thus indicating that both represent different entities, which were named CA and CB. The separate character of both enzyme forms is supported by the fact that CB under all conditions is degraded faster by the C-specific protease (E. Alhanaty et al. (1981) Proc. Natl. Acad. Sci. USA 78, 3492-3495) than CA, a phenomenon which is enhanced in both enzyme forms by substrate (Kemptide). The separation of both subtypes from each other is probably based on differences in isoelectric values (delta pH less than or equal to 0.5 units). The reason for the charge difference is not presently known. CA and CB do not differ significantly in their phosphate content. No differences between CA and CB have been detectable so far with respect to their migration in SDS gels, kinetic behavior regarding both substrates and cosubstrate, pH dependence, inhibition by regulatory subunits of holoenzyme type I (rabbit skeletal muscle) and of type II (bovine cardiac muscle), and inhibition by specific-heat and acid-stable inhibitor-modulator. The peptide pattern of both forms after limited proteolysis exhibits small differences.

The present report describes the distribution of tritium label after injection of newborn rats with [3H]6-hydroxydopamine ([3H]6-OHDA). The animals were injected either intracisternally (i.c.) or subcutaneously (s.c.), with or without pretreatment with nomifensine, which blocks the high-affinity uptake of both noradrenaline (NA) and dopamine (DA), and sacrificed at intervals from 40 min to 24 h post-injection (p.i.). In i.c. injected animals, tritium label is demonstrable as early as 40 min p.i. in neurons of all known NA and DA cell groups. In NA neurons, it is taken up into cell body, dendrites, preterminal and terminal axons. The intensity of neuronal labeling is highest within the first 4 h p.i. and decreases in most neurons with longer postinjection intervals. A significant proportion of both NA and DA neurons degenerate beginning 6 h p.i., the majority show morphological signs of the axon reaction 24 h p.i. Uptake of [3H]6-OHDA into serotonergic and non-catecholaminergic neurons is not demonstrable. [3H]6-OHDA is accumulated by the following extraneuronal cells of the CNS: ependymal cells, epithelial cells of the choroid plexus, subependymal macrophages, smooth muscle cells in the wall of large intraparenchymal blood vessels, meningeal cells and glial cells. The time course of accumulation and disappearance of the label varies among these extraneuronal elements. The meningeal cells show the highest labeling intensity and degenerate within 24 h p.i. After pretreatment of the animals with nomifensine, the uptake of [3H]6-OHDA into NA and DA neurons is totally blocked; by contrast uptake of the labeled drug into extraneuronal cells is not prevented. These findings show that [3H]6-OHDA is not only accumulated by neurons possessing the high-affinity uptake for NA or DA, but by numerous other, extraneuronal cells which also participate in the metabolism of catecholamines.

Sections of immature (postnatal day 5) mouse cerebral cortex was examined for several cell-type specific immunological markers. Glial fibrillary acidic (GFA) protein or vimentin were detected in astrocytic cell processes and--more rarely--cell bodies located in the superficial layers, but not within putative Cajal-Retzius cells (CRs). These cells did, however, react with cholera toxin, tetanus toxin and NS-4 antibodies. In agreement with previous ultrastructural observations, we conclude that CRs are neurons, or at least cells which display the basic characteristics of neurons.

Cell density countings and measurements of cortical thickness of animals treated neonatally with subcutan or intracisternal injections of 6-OH-DA were performed at five and fifteen days post-injection. Morphological changes were observed; however, these changes cannot be attributed without any doubt to the lack of catecholamine fibres.

Using an exogenous kinase, nuclear ribonucleoprotein complexes with sedimentation coefficients greater than 100S were phosphorylated in vitro before and after treatment with increasing concentrations of NaC1. The phosphorylation pattern of the proteins before raising the NaC1 concentration shows a major group of labelled proteins in the 30 000 to 40 000 MW range. Treatment of the complexes with 400 and 800 mM NaC1 produces a relative increase in the labelling of some polypeptides with the appearance of new labelled bands and the concomitant disappearance of several proteins. Even at the highest salt concentration used (1.2 M), it is still possible to identify a group of labelled polypeptides which are suggested to form the backbone structure of the nuclear RNP complexes.

Rat fetuses received tritiated thymidine on one of each of the following days of gestation: 9, 10, 11, 12, 13, 14 and 16. Animals were sacrificed on day 1 post partum. Perpendicular and tangential sections including temporal cortex were studied by electron microscopy and light microscopic autoradiography. Our results suggest that the formation of Cajal-Retzius cells (CRs) begins on day 12, reaches a peak on day 13, and continues on day 14. Earliest non-CR neurons of the temporal cortex (cells of the deepest stratum of layer VI) appear to be generated on day 13.

The catalytic subunit (C) of cAMP-dependent protein kinase holoenzyme type II from bovine cardiac muscle was separated by isoelectric focusing in Immobiline polyacrylamide gels into 9 protein forms. The major forms (i) appeared at pH 7.1, 7.4, 7.5, and 7.7, (ii) exhibited protein kinase activity and were inhibited by heat and acid stable inhibitor, (iii) represented approx. 30%, 4%, 64%, and 1% of the protein respectively, (iv) refocused in the same position from which they had been eluted from the first gel. Antibodies against C detected additional proteins at approx. pH 7.55, 7.75, and 7.8. Two more bands became detectable at approx. pH 7.3 and 7.45 by application of antibody against C beta (Uhler, M.D. & McKnight G.S. 1987, J.Biol.Chem. 262, 15202-15207). The relation of the different forms of C to the fractions CA and CB (Kinzel V. et al. 1987 Arch. Biochem. Biophys. 253, 341-349) is demonstrated.

Rhombencephala from rat embryos were processed as whole-mounts for immunocytochemical detection of monoaminergic cell populations, using antibodies to tyrosine hydroxylase (TH) and serotonin (5-HT). Specific advantages of the whole-mount technique over the classical serial-section method were that even isolated immunoreactive (IR) cells could be detected easily, and three-dimensional relationships could be ascertained without the need for serial reconstruction. Embryos between embryonic days (E) 12 and 16 (the day following nocturnal mating being considered as E1) were used in this study. Both TH and 5-HT immunoreactivities were already detectable at E12, even in the smallest embryos (crown-rump length: 6 mm), but there was a striking difference in the number and regional distribution of these two types of IR cells. TH was expressed in several cell groups located in the rostral rhombencephalon (the presumed anlage of the A4-7 complex) as well as in the caudal rhombencephalon (the presumed anlagen of groups A1-2 and C1-3), whereas 5-HT was expressed in very few cells located near the rostral border of the rhombencephalon (presumed anlage of the B4-9 complex). Although the three-dimensional distribution of the TH-IR cell groups underwent some modifications during the period studied, its general pattern remained relatively stable after E12. This contrasted with the sequential appearance of the 5-HT-IR cell groups and their spatial transformations during this period. Using the rhombencephalic isthmus as a landmark, we found that conspicuous 5-HT-IR fibre bundles penetrated into the mesencephalon from E13 onwards, but that the 5-HT IR cell bodies were exclusively located caudal to the borderline between the mesencephalon and the rhombencephalon (the rhombencephalic isthmus). We therefore suggest the term "rostral rhombencephalic raphe nuclei" for the rostral 5-HT cell groups instead of "mesencephalic raphe nuclei," which is a misnomer. Close spatial association between TH and 5-HT-IR elements was observed mainly in the caudal rhombencephalon, where 5-HT-IR fibres coursed through an area containing numerous TH-IR cell bodies (the presumed anlagen of groups A1-2 and C1-3).

Based on five of our own cases and the literature on hand the etiological, clinical, diagnostic and intensive therapeutic aspects of the syndrome are represented. Special emphasis is placed on the possible role of the oral contraceptives in triggering this syndrome.

Biochemical, hormonal, and behavioural aspects of the effects of prenatal treatment (foetal days 18 and 19) with 6-hydroxydopa (2 × 40 mg/kg) and DSP 4 (2 × 20 mg/kg) have been studied in the rat. The results of the catecholamine assays suggest that the 6-hydroxydopa treatment produced a transient decrease of noradrenaline concentration in the cerebral cortex, and a long-lasting decrease in the cerebellum, whereas DSP 4 produced a long-lasting decrease in the cerebral cortex and a tendency towards increase in the cerebellum. Assays of adrenocorticotropic hormone and corticosterone indicated a general tendency towards increase in base line as well as in moderate stress situations. The results of behavioural tests indicated hyperactivity and/or hyperreactivity, but not restlessness, and partly supranormal sensorimotor performances., (Copyright © 1985. Published by Elsevier Ltd.)

In a controlled clinical trial, the efficacy of an intravenous combination of cimetidine and pirenzepine (group A: 62 patients) was compared with that of an intragastric administration of a magnesium-aluminium-hydroxide concentrate (group B: 58 patients) in preventing visible and occult upper gastrointestinal tract bleeding in intensive-care patients. It was found that both forms of therapy had the same favourable effect on the extent and incidence rate of visible and occult gastric bleeding. The antacid was more effective than the cimetidine-pirenzepine combination in raising the pH level to 4 or higher (P less than 0.05). Intensive-care patients should, therefore, be treated with the antacid whenever possible, since it is equally effective as the cimetidine-pirenzepine combination in preventing bleeding from the upper gastrointestinal tract, whereas it is superior in elevating the gastric pH. Besides, the use of the antacid is also less costly.

The possible influence of noradrenaline (NA) upon cell differentiation has been studied by comparing NA-supplemented cultures of foetal pallial cells with control cultures grown in normal medium. Two days after plating, the cultures were processed for immunocytochemical detection of either an adhesion molecule and marker of early stages of neuronal differentiation (L1) or a marker expressed at relatively late stages (gamma-enolase). In both cases, the NA supplement reduced the expression of the antigen. The effects were more clear-cut for the late than for the early marker. In conclusion, the NA supplement to the culture medium, in our model, seemed to have a 'differentiation regulating' rather than a 'neurotrophic' function sensu stricto. It remains to be clarified, however, to which extent this finding can be generalized to in vivo situations.

Early cortical neurogenesis and synaptogenesis are discussed with reference to observations made in fetal and postnatal rat temporal cortex. Thymidine autoradiography was used to determine the time of origin of cortical neurons, particularly of layer I. Earliest neurons--CRs--form between FD 12 and 15, whereas the period of maximal formation of layer I neurons other than CRs is situated between FD 17 and FD 19. Neurons destined for the deepest part of layer VI begin to form at FD 13. Both types of early-forming neurons develop synaptic contacts by FD 16. From this stage onwards, the temporal cortex taken as a whole continuously contains synaptic contacts. However, a more detailed analysis shows that some at least of the early formed synapses are transitory: for example, the CRs, which receive dendritic synapses on FD 16 and somatic synapses on FD 17, apparently lose most--if not all--of these contacts towards the end of fetal life. Whereas CRs develop an important protein producing equipment during the neonatal period, younger neurons located in the same (first) layer form dendritic, somatic and somatofugal synapses.

The onset of synaptogenesis was studied in the temporal cortex of rat fetuses whose age ranged between 15 and 19 days of gestation. First synapses were found at a surprisingly early stage of cortical development: on day 16. These contacts showed relatively few vesicles and very inconspicuous membrane-thickenings. They were located in the marginal layer, above as well as below the narrow band formed by the newly arrived first neuroblasts of the prospective corticle plate. The postsynaptic structures were probably dendrites of the horizontally or obliquely orientated neurons scattered throughout the marginal layer (such neurons were seen even within the cell-dense band). On day 17, the cortical plate separated the differentiated cells definitely into a superficial and a deep population. As on the following days, synapses were found above and below the cortical plate but not within it. In addition to contacts showing the same features as those described on day 16, there were already synapses with numerous vesicles and clearly asymmetric membrane thickenings. On days 18 and 19 the borders of the cortical plate became more clear-cut. The well-differentiated neurons situated above and below this plate could now be identified as Retzius-Cajal cells of the prospective molecular layer and as polymorphous cells of the layer VI b respectively. The presence of axo-somatic contacts on these neurons provided direct evidence that both cell types are targets for synapses. Desmosome-like junctions were found even in the youngest fetuses studied. Their roughly symmetric membrane thickenings were clearly more conspicious than those of earliest synapses. Desmosome-like junctions occurred very frequently between structures which subsequently were never seen to become synaptically linked. During the entire period studied, numerous coated vesicles fused with cell membranes were noted. Such "open" vesicles were seen on neurons (sometimes in the immediate vicinity of synapses) but also on non-nervous, extracortical as well as intracortical structures. Thus there does not seem to be a specific relationship between desmosome-like junctions and coated vesicles on the one hand and synapse formation on the other.

We report on a case of transient neurogenic dysfunction of the urinary bladder caused by herpes genitalis in a renal transplant patient. The patient noticed a slow urinary stream 3 days after the vesicular stage of the herpes genitalis. After 9 days complete urinary retention and loss of sensation developed, necessitating the insertion of suprapubic tube. Symptoms and residual urine spontaneously disappeared after 20 days. After removal of the suprapubic tube the patient could empty his bladder completely with good stream. 45 cases of this kind have been described in the literature. the cause is a sacral meningo-radiculitis with herpes simplex virus leading to a transient neuromotoric paralysis of the bladder.

Newborn rats received an intracisternal injection of 6-hydroxydopamine (100 micrograms) within 16 h after birth. Treatment effects upon noradrenaline uptake (with or without desmethylimipramine pre-incubation), endogenous noradrenaline, dopamine, and serotonin were biochemically assayed. Noradrenaline uptake and endogenous noradrenaline content were permanently reduced to less than 5% of control values. Reduction of endogenous dopamine content was less marked: at day 60, values were about 40% of controls. Serotonin content remained unaffected. Cell density countings in postnatal day 15 temporal cortex revealed an about 16% reduction in layers II and III of treated animals. These modifications of cortical geometry were discussed with reference to measurements of cortical thickness and ultrastructural observations on postnatal days 2, 5 and 15. Both supranormal involution and growth processes might result from the neurotoxin treatment. Whereas some of the degeneration processes might be due o general cytotoxic effects, this is less likely for the supranormal growth processes.

The vascular system of the head is of great importance in most types of headache because of the sympathetic efferents supplying the vessels. From neuroanatomic data it is to be assumed that vascular diseases of different genesis and cardiovascular diseases may give rise to headaches. The connection between headache and hypertensin is discussed at length with reference to pathophysiology. Further, headache is presented as a symptom with reference to observations of our own cases of inflammatory diseases of the vessels, sinus thrombosis, vessel deformities, accidents in anticoagulant therapy with subdural and intraspinal haemorrhages, cerebrospinal lues and endocrinopathies. Tables and illustrations supplement the text.