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Venipuncture is a routine procedure performed at medical institutions for blood collection and blood donation, as well as for health screening and testing. Venipuncture is invasive and usually mildly painful, but it occasionally causes internal bleeding and chronic persistent pain, which is referred to as complex regional pain syndrome. The most common site of venipuncture is the upper arm. The present study macroscopically and anatomically ascertained positional relationships between cutaneous nerves and veins in the cubital (aka antecubital) fossa in many cadaveric dissections to determine the risk of peripheral nerve injury during venipuncture. We identified the most suitable venipuncture site in the upper arm. The medial cutaneous nerve of the forearm (MCNF) passed above the median cubital vein (MCBV) in 27 of 128 cases (21.1%), and was located inferior to the MCBV in 37 of 128 cases (28.9%). The MCBV also passed above the lateral cutaneous nerve forearm (LCNF) in 8 of 128 cases (6.2%). The LCNF was located deeper than the MCBV in 56 of 128 cases (43.8%). The distribution of cutaneous veins and nerves widely varies, and while no single area suitable for all individuals was identified, puncture of the MCBV near the cephalic vein is the least likely to cause nerve damage.

In this study, we isolated and characterized a murine counterpart of the human Arpp (hArpp) gene. Sequence analysis revealed that the murine Arpp (mArpp) gene is almost identical to the Ankrd2 gene, which has recently been isolated as a mouse gene induced in stretched skeletal muscle. The mArpp gene encodes a protein of 332 amino acids that contains four well-conserved ankyrin-repeat domains in the central portion of the protein. The amino acid sequence of mArpp protein (mArpp) is highly homologous to that of mouse cardiac-restricted ankyrin-repeat protein (Carp), which is proposed to be a putative genetic marker for cardiac hypertrophy. Immunohistochemical analysis revealed that mArpp is preferentially expressed in type 1 skeletal muscle fibers, and that mArpp is localized in both the nucleus and the sarcomeric I-band of muscle fibers, suggesting that Arpp may function as a nuclear and sarcomeric protein. Furthermore, mArpp was also expressed in neurons of the cerebellum and cerebrum, the islets of Langerhans in the pancreas, and the esophageal epithelium, suggesting that mArpp may play a functional physiologic role in brain, pancreas, and esophagus as well as in type 1 muscle fibers. Interestingly, although mArpp was localized in both nucleus and cytoplasm in neurons, its localization was restricted to nucleus in pancreas and esophagus, suggesting that intracellular localization of mArpp is regulated in a tissue-specific manner. Furthermore, we found that mArpp- and Carp-expression in skeletal muscle were markedly up-regulated after denervation. Although the elevated expression level of Carp was kept only for two weeks after denervation, that of Arpp was kept at least for 4 weeks, suggesting that mArpp and Carp may play distinct functional roles in denervated skeletal muscle.

We used triple-labeling immunohistochemistry in rat midbrain sections to identify dopaminergic neurons that contain either one or both of the calcium-binding proteins, calretinin (CR) and calbindin-D28k (CB). Midbrain dopaminergic neurons were immunohistochemically labeled for tyrosine hydroxylase (TH), CR, and CB. In the substantia nigra pars compacta (SNC), TH+/CR+/CB+ cells were clustered in two regions: the dorsal tier of the rostral SNC and the medial part of the intermediate SNC. The ventral tier of the rostral SNC mainly comprised both TH+/CR+/CB− and TH+/CR−/CB− cells. The lateral part of the intermediate SNC and the caudal SNC primarily consisted of TH+/CR−/CB− cells. Throughout the extent of the SNC, approximately half of the TH+ neurons were stained for neither CR nor CB, while the remaining TH+ populations were labeled for CR and/or CB. Throughout the ventral tegmental area, TH+/CR+/CB+ cells, TH+/CR+/CB− cells, TH+/CR−/CB+ cells, and TH+/CR−/CB− cells were found generally scattered, though the TH+/CR−/CB− cells were dominant in number. In the substantia nigra pars lateralis, interfascicular nucleus, and caudal linear nucleus, more than half of the TH+ cells were stained for both CR and CB. In the retrorubral field, two-thirds of the TH+ neurons contained neither protein. The present findings suggest that the SNC can be divided into subcompartments based on the distribution of dopaminergic neurons that contain calcium-binding proteins. Furthermore, because CR and CB likely contribute to calcium homeostasis by buffering intracellular calcium concentrations, midbrain dopaminergic neurons containing one or both of these calcium-binding proteins may have a higher calcium-buffering capacity than those lacking the two proteins.

The aim of the present study was to examine quantitatively whether two calcium-binding proteins, calbindin D28k and calretinin, are localized in oxytocin and vasopressin neurons of the supraoptic nucleus of the male rat. We used a triple-labeling immunofluorescence method with a confocal laser scanning microscope. Of the oxytocin-labeled cells, 70% were stained for both calbindin D28k and calretinin, 15% were stained for only calbindin D28k, 13% were stained for only calretinin, and 2% were stained for neither protein. Of the vasopressin-labeled cells, 73% were stained for neither calbindin D28k nor calretinin, 21% were stained for only calbindin D28k, 4% were stained for only calretinin, and 2% were stained for both proteins. Calbindin D28k and calretinin have been shown previously to contribute to calcium homeostasis by buffering [Ca2+]i. Therefore, these findings suggest that most of the oxytocin neurons may have a higher Ca(2+)-buffering capacity than most of the vasopressin neurons.

We found intense monoamine oxidase (MAO) activity in rat locus coeruleus (LC) neurons by means of a histochemical method using noradrenaline as a substrate. This MAO activity was abolished by clorgyline, a specific inhibitor of MAO type A. Fluorescence immunohistochemistry for tyrosine hydroxylase (TH) combined with MAO histochemistry revealed intense MAO activity in virtually all TH-immunoreactive LC neurons (i.e. noradrenergic neurons). The results indicate that noradrenaline produced in LC neurons might be degraded by MAO type A activity.

We examined whether dopamine-degrading activity of monoamine oxidase (MAO) is present in dopaminergic neurons of the rat brain. We employed a double-labeling procedure combining immunohistochemistry for tyrosine hydroxylase (TH) and enzyme histochemistry for MAO activity using dopamine as a substrate. The following dopaminergic cell groups were examined: A16 (glomerular layer of the olfactory bulb), A14 (hypothalamic periventricular region), A13 (zona incerta), A12 (arcuate nucleus), A11 (periventricular gray matter of the caudal thalamus), A10 (ventral tegmental area), A9 (substantia nigra pars compacta, SNC) and A8 (retrorubral nucleus). Although no MAO activity was detected in any of the TH-immunoreactive dopaminergic neurons, strong dopamine-degrading MAO activity was found in TH-positive neurons in the locus coeruleus (LC) (i.e., noradrenergic neurons). Our results indicate that dopamine-degrading MAO activity is very low in dopaminergic neurons compared to the MAO activity in LC noradrenergic neurons.

We examined monoamine oxidase (MAO) activity in the intermediolateral nucleus (IML) of the rat thoracic spinal cord by histochemistry with tyramine as a common substrate for both MAO types A and B. Light microscopy showed MAO activity in neuronal cell bodies, processes, and varicosities. Electron microscopic examination showed both MAO-positive and -negative neuronal cell bodies. In the stained cell bodies, histochemical reaction products were localized in the cytoplasm showing a selective association with mitochondrial outer membranes. MAO-positive axon terminals were often found in contact with MAO-negative neurons but only occasionally with MAO-positive neurons. MAO histochemistry in the IML was also performed using serotonin (a MAO type A preferential substrate) and beta-phenylethylamine (a MAO type B preferential substrate). Light microscopy identified MAO activity for serotonin in a plexus of varicosities but not in any neuronal cell bodies. The activity for beta-phenylethylamine was detected frequently in neuronal cell bodies but rarely in varicosities. Our findings indicate that two groups of IML neurons can be chemically distinguished, one contains MAO type B while the other lacks both MAO types A and B. In addition, many axon terminals contain MAO type A but only a few fibers include MAO type B in the IML.

The aim of the present study is to examine whether noradrenergic neurons of the locus coeruleus (LC) of the rat contain monoamine oxidase (MAO) activity. Sections were processed initially for MAO enzyme histochemistry using tyramine as a substrate, followed by fluorescence immunohistochemistry for tyrosine hydroxylase (TH). In the LC, virtually all TH-immunoreactive neurons (i.e., noradrenergic neurons) were also positive for MAO. No MAO activity was found in any TH-negative neurons. Neurons in the LC have previously been shown to form dopamine during noradrenaline biosynthesis and to produce serotonin from exogenously administered l-5-hydroxytryptophan. Moreover, dopamine- and serotonin-degrading MAO activity has also been found in LC neurons. Therefore, our results indicate that MAO activity is localized within noradrenergic neurons in the LC and is likely involved in the degradation of dopamine that is endogenously synthesized, and also in the elimination of serotonin that is produced from exogenous precursors.

Satoh et al. (1978a) demonstrated that Barrington's nucleus in the rat corresponds to the nucleus laterodorsalis tegmenti (TLD), immediately ventromedial to the rostral pole of the locus coeruleus (LC). To confirm this finding and to identify the course of the tracts and their terminals, we injected small amounts of HRP into the TLD, LC and the lumbar and sacral segments followed by the DAB and TMB reaction. Injection of HRP into the TLD resulted in the anterograde staining of descending fibers in the latero-ventral part of the lateral funiculus, which mainly terminate in the intermediate area of the sacral segments, and in the retrograde labeling of a large number of cells in the intermediate area of the sacral segments. After injection of HRP into the sacral segments, marked labeling of many TLD cells was demonstrated in contrast to that of only a small number of LC cells. On the other hand, after injection of HRP into the LC, a moderate number of descending fibers were found in the ventral part of the lateral funiculus, with small numbers in the apex of the dorsal horn and ventral funiculus, mainly ending in the intermediate gray of the lumbar segments. Moreover, moderate numbers of retrogradely labeled cells were revealed in the intermediate area of the lumbar segments. From these results it may be concluded that the reciprocal interrelation between the TLD and intermediate gray of the sacral segments is more important for the micturition reflex than that between the LC and lumbo-sacral segment.